Sweden is hosting the European Spallation Source (ESS), which will be the worlds most brilliant neutron source once it is commissioned. In order to take best benefit of the capabilities of high-end facilities an ecosystem of smaller sources is required but currently Sweden has no neutron source allowing materials research. As a consequence of that the number of experts in the field has...
Curved 3He detectors used on single crystal and powder diffractometers are among the most advanced detectors in neutron scattering science. They provide high detection efficiency, low gamma background, and high position resolution, with no parallax error in the plane perpendicular to the detector axis. 6 of these detectors are currently in operation worldwide: D19, D20, and D1B at ILL, HRPT at...
We present the development of a model to describe the interactions of neutrons in normal and superfluid He-4 at temperatures below 2.17 K. The model was constructed based on the separation of the single-phonon and multi-phonon excitations at low temperatures. Below around 3.4 Å-1, the single-phonon excitations are described exactly by the dispersion relation, while the multi-phonon excitations...
Time-Of-Flight Neutron Diffraction (TOF-ND) analysis was performed to obtain a quantitative identification of the mineralogical phase composition of historical mosaic glasses. The presented work is part of a multi-technique characterisation of such mosaic tesserae with the aim of obtaining a detailed quantitative description of the elemental and phase composition in a completely...
The ARGITU project is one of the initiatives framed within the joint European strategy to develop the next generation of high-current accelerator-driven neutron sources (HiCANS). In this envisioned facility, a high current proton beam (E=31.5 MeV) hits a beryllium target, producing neutrons by nuclear processes that can serve to run a suite of up to four neutron scattering instruments per...
Additive manufacturing (AM) has gained significant importance in the past years and is regarded to have the potential to revolutionize the manufacturing processes of materials, enabling complex geometries that are not feasible to be built using conventional manufacturing processes. The increasing complexity of AM-built components demands advanced spatially-resolved characterization techniques...
Neutron imaging has seen a remarkable transformation from a non-destructive testing tool spotting cracks on millimetre length scales in industrial components to a diverse research tool in material science and beyond. Direct spatial resolutions of a few micrometers are state of the art today, but also structural features down to the Angstrom regime can be probed through modalities sensitive to...
Three-axes spectroscopy (TAS) is a well-established method that has not substantially changed in the past decades of its use. Nowadays, with increasing demand and limited availability of TAS, application of AI methods is one option to increase their efficiency. From an AI perspective, TAS experiments collect noisy observations of a 2D intensity function to investigate a material of interest....
Molecular deuteration of organic compounds and biomolecules significantly increases options available in characterisation and complex structure function investigations using neutron scattering and reflectometry, nuclear magnetic resonance (NMR), mass spectrometry (MS) and other techniques by providing contrast and improved data resolution and creates functional materials with superior...
For the examination of the pottery forming techniques, two series of experimental vessels have been made with three different, historical forming techniques (coil-building, wheel-shaping, wheel-throwing). Cubical samples from each experimental vessel were measured by SANS in three perpendicular orientations, and the recorded anisotropic scattering maps were analysed in 2D. The measure of...
The neutron Electric Dipole Moment (EDM) has attracted interest as a promising channel for finding new physics for a long time. The existence of a neutron EDM would violate CP symmetry given CPT conservation. This new source of CP violation could explain the baryon asymmetry of the universe. The BeamEDM experiment aims to measure the neutron EDM using a novel technique which overcomes the...
The structural chemistry of NaNiO2 is driven by the Jahn-Teller distortion. NaNiO2 consists of alternating layers of edge-sharing NiO6 and NaO6 octahedra. The high-temperature phase has a rhombohedral symmetry, but with cooling there is a monoclinic distortion, as a result of a cooperative Jahn-Teller-driven elongation of the NiO6 octahedra, with the axis of elongation parallel for all...
INES is a powder diffractometer operated at ISIS, in which thermal and epithermal neutrons are used to study elemental and isotopic composition of materials, with special application to cultural heritage studies.
In this talk we present the comparison of the average neutron fluence rate measured at INES with the predictions based on the FLUKA_CERN simulations.
The total integrated flux, the...
Inelastic neutron scattering is instrumental in making key discoveries in a broad range of materials, such as superconductors, multiferroic materials and quantum magnets. However, the applicability of the technique is limited by inherently weak signals, leaving parametric studies as a function of sample environment parameters relatively inaccessible.
BIFROST, currently under construction...
Chasing new states of quantum matter is a central element in condensed matter physics, motivated both by fundamental curiosity but also by the need for a better understanding of many-body quantum effects for future technologies. Of particular interest are frustrated systems such as the Shastry-Sutherland (SS) model consisting of spin pairs (dimers) embedded in a square lattice. The model has...
In 2021, the global production of ammonia was estimated at around 200 megatons, which makes ammonia the second-most produced chemical in the world. Among different ammonia synthesis routes, the most prevalent one is the Haber-Bosch process, occurring over the iron catalyst at high pressures (more than 150 bar) and high temperatures (more than 400⁰C). However, it has been recently demonstrated...
Many pharmaceuticals products are stored as frozen solutions or in amorphous solid (lyophilized) phases to minimize chemical and physical degradation during their shelf life.
However, freezing and drying per se could also destabilize proteins. There are multiple protein degradation pathways, including, e.g., oxidation, deamidation, and aggregation. Protein aggregation, in particular, can...
The Neutron Scattering User Program at Oak Ridge National Laboratory in Oak Ridge, USA has long needed a single-crystal alignment station co-located with its Time-of-Flight Spectroscopy instrument suite. The First Target Station (FTS) at the Spallation Neutron Source (SNS) has an open beam port located at position 16a which looks at a poisoned-decoupled thermal-water moderator. The...
Wearable renewable energy generators are an attractive alternative to battery-based systems and can generate power up to a few Watts for portable electronic equipment. Although the most inorganic semiconductor materials are brittle at room temperature (RT) the Ag2SeTeS)1 chalcogenides show exceptional plastic deformability and high thermoelectric performance making them suitable materials for...
Molecules are promising building blocks for future generations of functional materials. A particularly interesting niche are molecules that contain metal-ions in different oxidation states, since double exchange can contribute to the molecular magnetic properties in addition to conventional Heisenberg exchange. The most promising prospect coming from competition between these exchange...
The search for novel materials exhibiting non-trivial properties is the main task of solid state research. Ranging from high temperature superconductivity over quantum computers, novel batteries to spintronics and multi-functional materials, this field spans a wide range of disciplines and material types. One specific field of interest within magnetism is multiferroicity where especially...
A chiral spin liquid state is discovered in the highly frustrated, layered kagome system YBaCo3FeO7 by polarized diffuse neutron scattering [1]. From the antisymmetric part of scattering, related to vector chirality, we determine the chiral correlation function by Fourier analysis. The chiral short-range order indicates the emergence of chiral lumps. It can be described by cycloidal waves,...
X-ray and neutron scattering are widely used powerful techniques for probing the physical structure of materials at the molecular and supramolecular scale. With the simultaneous advent of high-speed detectors, previously unimaginable time-resolved in situ and high throughput photon and neutron experiments have become possible, with the subsequent explosion of data volumes. Data analysis is...
Clathrate hydrates [1] are water-based solids with large unit cells which show promise as moderators for use in the development of new and more intense sources of very cold neutrons (VCN). Such sources have the potential to enhance existing neutron scattering techniques as well as to increase the reach of particle physics experiments employing beams of slow neutrons
The moderation potential...
Non-stoichiometric oxides with Ruddlesden-Popper structure type and the chemical formula A2BO4 (A = rare earth, B = transition metal) can uptake extra O-atoms on interstitial lattice sites (Oint). Due to their high mobility even at room temperature, long-range O-ordering up to the sub-mesoscale is observed in several A2BO4+d phases, which, together with charge and spin ordering, results into a...
Following the discovery of a quantum-limit magnetic Chern phase in TbMn$_6$Sn$_6$ [1], and the observation of a large topological Hall effect (THE) related to the field-induced magnetic phases in YMn$_6$Sn$_6$ [2], the magnetic topological metal series RMn$_6$Sn$_6$ (R=Gd-Yb, and Y, Lu etc.) [3], that possess an ideal kagome lattice of Mn, have emerged as a new platform to explore exotic...
We report high-resolution neutron spectroscopy on the archetypal heavy fermion material CeIn3 that exhibits an antiferromagnetic (AFM) order below TN= 10.1 K. Increasing pressure suppresses the AFM state to zero temperature resulting in a quantum critical point, the critical fluctuations of which are believed to mediate unconventional superconductivity. Previous neutron results with moderate...
Polarization analysis provides profound additions in knowledge for the field of soft condensed matter research. The ability to study dynamics of incoherent and coherent scattering contributions separately gives unique information on the cooperative vs local dynamics of a system. The JCNS is interested in exploring new instrumentation ideas as a polarization analysis upgrade to our SHPERES...
Neutron diffraction instrument DREAM is among the first instruments to be constructed at the European Spallation Source (ESS) in Lund, Sweden. The Diffraction Resolved by Energy and Angle Measurements (DREAM) instrument is being built as an in-kind contribution from the Jülich Centre of Neutron Science (Germany) and Laboratoire Leon Brillouin (France)1. The instrument views both cold and...
The ac current-driven motion of spiral spin textures was shown to give rise to emergent electric fields that provide functionality as an electrical inductor - the so-called emergent inductance phenomenon [1-2]. Most recently, the first such system to display this phenomenon beyond room temperature was identified to be the helical magnet YMn6Sn6 [3]. To deepen the microscopic understanding of...
Hexaferrites are important metal oxides, widely used as both permanent magnets and microwave absorbers. Recently, hexaferrites have attracted great interest, because they show magnetoelectric effects at room temperature. [1,2]
We have synthesized W-hexaferrites with varied Co/Zn ratio and investigated the magnetic order using neutron powder diffraction. In SrCo2Fe16O27 and SrCoZnFe16O27 a...
Using neutron spin echo spectroscopy the dynamics of short unentangled tracer chains in the melt of a highly entangled polymer matrix has been investigated [1]. Independent of the tracer chain length the center of mass mean square displacement (MSD) is sub-diffusive at short times and crosses over to Fickian diffusion at longer times. The obtained diffusion coefficients on the nm scale agree...
At JCNS we develop a technical design for a future high brilliance neutron source HBS. The very compact design of the neutron source allows to extract larger phase space volumes from the neutron moderators as compared to existing facilities, where the minimum distance between the moderator and extraction system and/or first choppers poses a significant constraint.
In this presentation we...
Pyrochlore Heisenberg antiferromagnets (HAFs) are commonly studied as an archetypal example of three- dimensional geometrical magnetic frustration. The study of these so-called “highly frustrated magnets” provides a route to access a large variety of fascinating emergent low-temperature magnetic states including spin-liquids, spin-glasses, spin-ices, and fragmented spin-structures....
For small angle neutron scattering (SANS), neutron reflectometry (NR), and neutron protein crystallography (NPX), using deuterated samples has numerous benefits. The molecules that are of most interest include proteins, lipids, fatty acids, small organic molecules, surfactants, and membranes. For SANS, NR deuteration is most commonly used to enable contrast variation, allowing scientist to...
The molecular deuteration of organic compounds and biomolecules is an essential requirement in many neutron scattering and other characterization techniques. This need has been increasingly recognized by neutron facilities and research groups around the world. The custom synthesis of deuterated molecules can be laborious and costly to achieve optimum chemical as well as isotopic purity. Users...
In order to provide users of the neutron scattering instruments at the MLZ with the appropriate partially or fully deuterated materials, JCNS has started last year a deuteration service, primarily from our core competences of polymers, ethoxylation and organic synthesis.
Based on our long standing expertise in synthesizing soft matter materials, we offer the deuteration of various polymers,...
The Institute for Research into the Fundamental laws of the Universe (Irfu) at CEA, France, is developing and providing accelerator parts for various national and international projects.
Our competences and realisations on high intensity light ion accelerators suitable for the development of Compact Accelerator-based Neutron Sources will be presented.
Increasing demand for neutron detectors and the shortage (rise of the cost) of the Helium-3, opened a new era for using solid neutron converters. Our group at the University of Bonn is developing three different types of detectors by combining solid converters with high spatial and time resolution of a Timepix3-based readout. They are all thermal neutron sensitive.
One of the detectors is...
The European Spallation Source (ESS) will operate a suite of diffractometers, with the DREAM diffractometer [1] among the first instruments to be commissioned with neutrons. In order to take full advantage of this powerful source and to ensure smooth operation even for first-time users, the ESS Data Management and Software Centre is developing an integrated data pipeline linking all the steps...
Temperature variations have a big impact on the bacterial metabolism and death, yet an exhaustive molecular picture of these processes is still missing. For instance, whether the thermal death is determined by the deterioration of the whole or a specific part of the proteome is hotly debated. In our work, by monitoring the proteome dynamics of E. coli we show that only a minor fraction of the...
Cell membranes are complex objects made by several different molecular species. One of their most significant complexities is compositional asymmetry, key factor claimed to be associated to functional and structural roles. Nonetheless, membranes asymmetry is often hard to be reproduced in mimics. Experimental models, bearing forced membrane leaflets asymmetry in the form of dispersed...
After the static criticality of 3-picolin/D$_2$O and 3-picolin/D$_2$O/sodium tetraphenylborate having been identified to be of the 3d-Ising and 2d-Ising type, respectively, we investigated the dynamic criticality of the two systems using dynamic light scattering and neutron spin-echo spectroscopy. The first method yields the hydrodynamic diffusivity, while the second method observes the...
Endurance encompasses more than 30 new or upgraded instrument and infrastructure projects, rolled out over 8 years between 2016 and 2023 and with a financial envelope of nearly 60 M€. Many new or upgraded instruments have already been deployed and in user-operation including: the fission-fragment gamma ray spectrometer, FIPPS; the upgraded cold-neutron TOF spectrometer IN5; new thermal TOF...
Neutron radiography plays an important part in the diagnostic repertoire of nondestructive inspection techniques providing information of the inner part of an object often not accessible by any other means. Since the start-up of n_TOF’s second experimental area (EAR2), the possibility of diversifying the capabilities of EAR2, profiting from a high instantaneous neutron flux, were exploited....
5 min intro and 15 min talk
Chopper spectrometers produce large 4-dimensional inelastic neutron scattering (INS) datasets, allowing investigations of vibrational and magnetic properties of materials over large regions of momentum-energy (Q-E) space. While software (e.g. Horace) exist to enable visualisation and analysis of such data, computational challenges remain for the simulation and fitting of vibrational...
Cooling a liquid and avoiding crystallization the viscosity will increase dramatically and finally the viscous liquid will arrest into the glass state. This process is accompanied by a slowing down of the structural relaxation process. However, it is unclear whether there exists a particular, universal temperature range at which the slowing down sets in.
We investigated the dynamics of liquid...
Interactions of critical fluctuations in combination with an increased phase space may drive a second order phase transition first order. Using small angle neutron scattering (SANS) and modulation of intensity with zero effort (MIEZE) spectroscopy in combination with measurements of the magnetic, thermodynamic, and transport properties, we have investigated the fluctuation-induced first-order...
Hybrid Organic-Inorganic Perovskites (HOIPs) have attracted an unprecedented attention as promising candidates for the next-generation of photovoltaic materials due to their exceptional energy conversion rates. Moreover, a better understanding of their remarkably soft atomic structures and their stabilization mechanisms is still necessary [1,2]. In this contribution we present an extensive...
Recycling of rare-earth elements contained in magnetic materials is an important step towards sustainability of valuable resources. The challenges are many and such tasks require analytical techniques to characterize the composition of the waste flows. Characterization of the rare-earth elements in industrial scale is a new challenge to take up. The existing traditional methods used for...
Yttrium iron garnet (Y$_3$Fe$_5$O$_{12}$) has, since its discovery in 1957, fundamentally contributed to the development of important research fields such as spintronics, magnonics and hybrid quantum information systems. Iron garnets incorporating magnetic rare-earth ions are relatively less well-known, but have also been studied for their interesting spin transport phenomena, magnetoelectric...
The first Neutron Spin Echo (NSE) instrument, IN11, was in user operation for 40 years. The newest spin echo instrument WASP took the relay and just had its first full year of user operation. I will use this occasion to review how the design of the wide angle NSE spectrometers has developed over the years.
Apart from WASP, all non-resonant Neutron Spin Echo spectrometers use the basic IN11A...
The quantum spin liquid (QSL) phase is of immense interest to condensed matter physicists, and have been studied for decades. With a Kitaev model that is exactly solvable and gives a QSL ground state, α-RuCl3 is a promising Kitaev QSL candidate. Above the critical magnetic field Bc~7T and below T~6K there is evidence for the fractional excitations in the QSL phase. Although previous inelastic...
Modern materials often exhibit a considerable portion of structural disorder, playing a key role in their functionalities. In order to characterise local atomic arrangements and short-range correlations one has to study the shape of Bragg lines and the distribution of diffuse scattering below and between them.
To extract information from experimental data one has to compare model-based...
Although softness is a concept used in everyday life, its precise quantification is still far to be achieved. This is a fundamental step to build bridges between model systems which are largely studied and bio-relevant materials. The softness of a building block in solution plays a key role in determining the macroscopic properties of the material, such as viscosity or apparent yield stress....
Within the framework of the Jülich High Brilliance Neutron Source (HBS) project, a high current accelerator based neutron source (HiCANS) is developed. The main power-limiting factor is the target that releases neutrons via nuclear reactions from the impinging protons. The neutron yield of these nuclear reactions is quite small. This is compensated with a high proton current which leads to a...
Most of the spiral magnetoelectric multiferroics investigated in recent years are geometrically or exchange frustrated magnets with low magnetic transition temperatures. The exceptional stability of the spiral magnetic order (at T$_S$) in the layered structure of YBaCuFeO$_5$ [1,2] involves a non-conventional mechanism (“spiral order by disorder”) theoretically developed by Scaramucci et al....
Sickle cell disease (SCD) is a genetic blood disorder, inducing severe anemia. It results from the polymerization of the oxygen-carrying protein hemoglobin found in red blood cells (RBC), which leads to a deformation of the cells to rigid, sickle-like shape under certain circumstances that will obstruct capillaries vessels, and will ultimately induce the disease of different organs. The...
HiCANS are new neutron sources of a very high interest for the future. However some major technological issues remain; one the biggest one being the development of targets able to sustain the high intensity proton beam during a time long enough to have a smooth operation of the source. We will present the developments made in Saclay on high temperature Berylium targets. Two different targets...
Glassy metals provide an attractive route to low-scattering window materials for neutron instruments and sample environments. These can improve significantly efficiency in use of neutrons. Studies with AMLOY-ZR01, a zirconium based bulk metallic glass from Heraeus have shown high transmission and low levels of small-angle scattering as well as the complete absence of Bragg diffraction peaks...
A correlated liquid state was reported in the pyrochlore Ce$_2$Sn$_2$O$_7$. Its nature remained elusive, but with additional knowledge on the crystal-electric field scheme, the case of cerium pyrochlores was further investigated based on degrees of freedom having both magnetic dipole and magnetic octupole components. A number of recent studies all point towards a quantum spin ice (QSI) based...
After completion of assembling the hot commissioning of the compact neutron source CANS facility “LvB” in Martonvásár will start in January 2023. The system consists of a 35 keV proton ion source, a 2.5 MeV RFQ proton accelerator a thin Li layer target, Pb reflector and bi-spectral thermal-cold low dimensional moderator, that can serve up to 8 neutron scattering instruments. In addition, a...
Terahertz time domain spectroscopy (THz-TDS) revealed that fast (rotational) water dynamics depend on phospholipid headgroup structure by comparing PC and PE [1], but the comparison between them for the loosely and tightly bound (translational) hydration water (HW) observed for DMPC by quasi-elastic neutron scattering (QENS) [2], is still not revealed. We have done QENS experiments on the...
Fast and efficient hydrogen storage is one of the key components for the use of hydrogen in a sustainable energy economy. Reactive Hydride composites have been considered for some time as potential solid state storage systems, among others also the amide based mixture Mg(NH$_2$)$_2$ + 2 LiH. The kinetic performance of the hydrogen exchange reaction in this system is significantly enhanced by...
High-entropy alloys (HEAs) receive attention due to their diverse and often extraordinary properties. They are solid solutions where minimum four different elements randomly occu-py a single crystallographic site in structures such bcc and fcc. Because of the random distri-bution of metals, there is a large variety of different nearest-neighborhood environments surrounding the interstitial...
The way to identify and characterize potentially interesting neutron-moderating materials is to measure their neutronic properties: vibrational density of states (VDoS) and total cross-section. The idea behind the VDoS measurements is to look for low energy vibrational modes that can enable efficient moderation of neutrons in the so-called cold energy region.
TOSCA instrument [1] at the...
Protein dynamics play a vital role in biology. Quasi elastic neutron scattering is an ideal method to access these dynamics. Normally data analysis is performed based on the assumption that the scattering spectrum is incoherent. In order to be observe the full range of protein dynamics it is necessary to perform the experiments in solution. This solution is usually a fully deuterated buffer,...
The importance of sustainable human nutrition is growing with the increasing effects of the climate change. Usually, emulsions systems like milk are composed of unsustainable, animal derived milk proteins, phospholipids, oil and water. To increase the sustainability of emulsion systems, milk proteins are substituted with sustainable plant proteins, whereby the stabilization mechanisms, and the...
Switchable functional molecules capable of producing mechanical work constitute an active focus in nanotechnologies as they can be a source of components for molecular-based devices and materials. In particular, the dynamic nature of mechanically interlocked molecules allows their components to undergo relative internal movements, which can be exploited in translation and circumrotation. When...
A fundamental step for the application of ethylene in derivatives is its separation/ purification from ethane after being obtained by naphta or ethane steam cracking. The state of art method for such task is cryogenic distillation, which lies as one of the most energy consuming industrial processes nowadays.
A highly promising alternative method for this issue is the use of advanced porous...
Topological states, potentially leading to the formation of Majorana fermions, have been predicted to emerge in heterostructures of an s-wave superconductor (SU) and a semiconductor (SE) with large spin orbit coupling and split band structure [1]. Incorporation of ferromagnetic materials, such as ferromagnetic insulators (FMI), into the het-erostructures constitutes a promising route for...
The formation and disintegration pathways of polymeric nanoparticles are of key importance for their use for the transport and release of substances. Poly(N-isopropylacrylamide) in aqueous solution forms nanoparticles (“mesoglobules”) above its cloud point, which depends on pressure. In the temperature-pressure frame, the coexistence line is an ellipse with a maximum at ~60 MPa and 35 °C....
For polycrystalline materials, key material properties including strength, deformation behavior, magnetic susceptibility, weldability and stress corrosion cracking resistance depend significantly on the texture of the crystalline microstructure. Conventional assessment of texture is either limited to thin surface regions or it is destructive while only probing small fractions of a bulk...
Magnetic multilayers (MMLs) composed of alternating ferromagnetic / heavy-metal layers are one of the most technologically promising classes of skyrmion-hosting systems due to number of their advantages, such as skyrmion stability at room temperature and their tunability via layer engineering [1]. Through the combination of broken inversion symmetry and spin-orbit-coupling at the asymmetric...
Multiferroic Ba$_2$CoGe$_2$O$_7$ is well known for having an unconventional metal-ligand d-p hybridization mechanism responsible for the magnetically induced ferroelectricity [1,2]. It exhibits many exotic quantum phenomena, and among them anisotropic spin excitations and self-tunable single ion anisotropy under external applied magnetic field have been observed recently, using inelastic...
Mutliferroic materials are under investigation due to the prospect of controlling the magnetic state with electrical potentials or vice versa. We present an investigation of thin film multifferroic CoCr$_2$O$_4$ (CCO) in pure and Fe-doped form grown with different crystallographic orientation and strain on either MgAl$_2$O$_4$(001) (MAO) or Al$_2$O$_3$(0001) (ALO) substrates. Bulk CCO shows a...
The Marmot project is a new type of multiplexed secondary spectrometer for cold triple axis instruments.
It is based on a novel concept of energy analysis, using a large array of bent silicon blades and a position sensitive detector. By its particular geometry, it allows for continuous analysis of the neutron energy in a wide energy range (about 3.5 to 7 meV) and with a large divergence....
We present novel advances in the implementation of Neutron Resonance Transmission Imaging (NRTI), a non-destructive 2D quantitative elemental analysis technique, performed at the Italian Neutron Experimental Station (INES) beamline operating at the ISIS neutron and muon source, UK.
Neutron spallation sources have high epithermal neutron fluxes, which is a profitable energy range for elemental...
Myelin is a natural and dynamic multilamellar membrane structure that continues to be of significant biological and neurological interest, especially with respect to its biosynthesis and assembly during its normal formation, maintenance, and pathological breakdown. To explore the usefulness of neutron diffraction in the structural analysis of myelin, we investigated the use of in vivo labeling...
Heat transport properties in solid materials are driven by the accumulative contributions of phonons spanning a wide range of mean free paths. Porous, hygroscopic, nanocellulose foams exhibit super-insulating properties, highly dependent on their moisture content, and through theoretical estimations and simulations, it has been shown that the heat transfer in such materials is dominated by...
The advent of compact high-brilliance neutron moderators has raised the question how to efficiently extract and transport neutrons from such sources while maximizing the brilliance transfer to an instrument. Nested mirror optics (NMO) offer a viable and flexible solution for this task by circumventing the under-illumination associated with long neutron guides. A basic version, consisting of an...
A way to reduce the world’s reliance on conventional fuels is to obtain cost-competitive alternatives to convert and store energy. This could be done by implementing cheap storage devices, such as Na-Ion batteries [1], which are the focus of our investigations. During the first part of the project, major attention was dedicated to the fabrication of Prussian blue analog-based batteries, which...
Multiferroic materials have been intensively studied these last decades for their interesting physics and their promising magnetoelectric applications [1]. Materials having a crystallographic chirality are particularly interesting in the sense that their structure couples to magnetism and can display novel magnetoelectric coupling. This is the case of MnSb$_2$O$_6$ which crystallizes in P...
A S = $1\over2$ triangular lattice Heisenberg antiferromagnet (TLHAF) is its typical example, where combined effects of geometrical frustration and quantum fluctuations lead to stabilization of novel spin structures as function of external magnetic field. Hexagonal Ba$_3$CoSb$_2$O$_9$ (BCSO) compound exhibits magnetic properties typical of an ideal S = $1\over2$ TLHAF, making it a perfect...
A major milestone in cold neutron moderator developments has been the invention of low-dimensional geometries [1], such as the butterfly moderator of ESS. Monte-Carlo simulations have shown that if para-hydrogen is used as moderator material, these novel moderators can increase significantly the brightness, desired by most types of neutron instruments. Various designs were extensively studied...
Scientific investigations and archaeometric studies have played a major role in the field of archaeology, especially with regard to materials that have been transformed through human activity, like metals. In this talk, I will give an overview of how neutron imaging can be useful to improve our knowledge of ancient manufacturing processes of metals, their technological evolution over the...
5 minutes intro and 15 minutes talk by the awardee.
Neutron Physics Laboratory (NPL) of CANAM infrastructure (operated by Nuclear Physics Institute Řež), canam.ujf.cas.cz/npl, and its instrumentation for investigation of structure and microstructure of advanced materials will be presented. NPL consist of five neutron diffractometers (residual stress scanning, powder diffraction, small-angle neutron scattering, in-situ thermomechanical tests and...
Polymer electrolyte membranes (PEMs) are of great interest as solid electrolytes for applications such as fuel cells, water treatment and electronic devices. Typically, PEMs are composed of the hydrophobic polymer matrix, hydrophilic polymer chains with ionic groups. Upon hydration, ionic groups absorb water resulting in the formation of ion channels that phase-separated from the hydrophobic...
Water and all its ice forms play a central role in everyday life and science and, as a consequence, the scientific community strives to deepen the knowledge about the polymorphism of ice. Beside this, the investigation of the phase diagram of the solid mixture of water and molecular hydrogen at high pressure has been particularly prolific and associated with exciting discoveries. Several solid...
Conservators tasked with preserving waterlogged archaeological wood, such as artifacts found at the bottom of lakes or seas, must use reversible treatments that impart structural soundness on the often heavily decayed objects. They must also provide historical wood with appropriate resistance against further biodeterioration. Current treatments, while reversible, do not necessarily protect...
Quasi-elastic neutron spectroscopy of liquids is in common usage at the ISIS Neutron and Muon Source, UK, to examine incoherent (non-propagating) dynamical properties, such as diffusion constants and local internal molecular modes. However, it is much more difficult to measure coherent excitations in liquids with neutrons due to their kinematical constraints - namely the rather limited range...
Simple molecular systems, like water, methane, ammonia, hydrogen, and their mixtures are of para-mount importance for many fields, ranging from energy storage applications to condensed matter and planetary physics [1-2]. These systems are widespread on Earth, in various planetary bodies in the solar system and in newly detected water-rich exoplanets, and constitute an incredibly rich gas...
Analogous to electronic magnetism, a nuclear spin system can undergo a transition from a paramagnetic to a ferromagnetic or antiferromagnetic state subject to mutual dipole-dipole interactions. This exotic phenomenon, known as nuclear magnetic ordering (NMO), has only been observed in a few cases that form simple atomic single crystals. We recently developed a model to describe NMO in...
We review recent inelastic neutron scattering experiments aimed at the investigation of still open issues in the dynamics of liquids at the nanometer and picosecond scales. It is shown that the interpretation of experimental results is put on solid grounds by the application of modern methods of analysis and lineshape modeling which ensure the fulfillment of fundamental physical properties...
In cyanobacteria, photosynthesis is initiated by light absorption in protein complexes referred to as phycobilisomes (PBs). In excess light, photodamage to the photosynthetic apparatus is prevented by non-photochemical quenching (NPQ). This adaptive process responsible for high light tolerance is realized by the interplay between the light-harvesting PBs, a light-sensitive effector of NPQ...
Cells, the basic units of living organisms, are well delineated and separated from the external environment by membranes. Capable of both enclosing the cellular constituents and allowing exchanges with the outside world, these membranes are only a few nanometers thick. To study the dynamics and function of these amazing objects, physicists first seek to understand their structure. This...
Polymers are key elements in modern material science, and, since the first polymer synthesis in 1907, tremendous progress in polymer chemistry were made. Today, an endless assortment of polymers – whose properties are adapted to specific needs – is available. In many cases, a thin polymer film, the coating, is sufficient to impart desired properties to the material.
One of the most employed...
Polymer-based organic solar cells receive a growing interest and achieve a substantial progress concerning device efficiency and lifetime during the last years. Moreover, the potential low fabrication costs, fast energy payback times and the use of lightweight materials make them very appealing. In terms of champion device efficiency, values above the 18% limit were reported recently. Mainly...
Protein Production Sweden (PPS; [www.gu.se/pps][1]) is a new national research infrastructure established in 2022 and focused on the production and purification of protein reagents for primarily Swedish researchers, both from academia and commercial entities. Well-established protein production platforms from five universities (the University of Gothenburg (host), Karolinska Institutet, KTH...
Amorphous Rare-Earth - 3d Transition Metal alloys (RE-3d TM) are fascinating magnetic materials due to the easy, straight-forward tunability of their magnetic properties, depending on temperature and the concentration ratio between the RE and 3d TM components. In this presentation, DyCox thin films sandwiched by two thin Ta layers are discussed that show various intriguing phenomena, e.g. a...
Spin liquids–strongly correlated, yet disordered magnetic ground states–are extremely attractive from fundamental as well as application point of view [1,2]. While their realizations are scarce and not yet completely understood, they are praised as a platform for quantum computers. A classical spin liquid is predicted for the Ising antiferromagnetic triangular model, while additional...
The Reactor Institute Delft (RID) is the only research facility in the Netherlands that uses neutron- and positron beam line instruments for academic research. The 2.3 MW research reactor not only facilitates beam-line instruments that offer the unique opportunities of this special radiation but operates irradiation facilities where isotopes can be produced for heath research or element...
For many experiments performed at the cold-neutrons fundamental physics instrument PF1B at ILL, the polarizer is an essential component [1]. Placed after the guide exit, it should produce a large-area, intense and well polarized “white” beam spanning a broad wavelength range (from 0.2 to 2.0nm). Until recently, a “Schaërpf-type” bender based on Co/Ti supermirrors was used, showing 98.5%...
Ulrich Schmidt on behalf of the aSPECT collaboration
The aSPECT collaboration published in 2020 the most precise value on the electron-antineutrino correlation coefficient $a=-0.10407(82)$ of neutron $\beta$-decay. The value of this correlation coefficient $a$ is directly linked to the $\lambda$ parameter of the Weak Interaction of the Standard Model. The value for $\lambda$ obtained in...
Milestone steps have been taken recently to meet the requirements of experimenters using cold (CN) and very cold (VCN) neutrons. In fact, despite the wide range of experiments that can benefit from the long wavelength neutrons, e.g. in the study of slow dynamics within large structures, or in the study of the neutron itself as a quantum object, their use remains limited compared to thermal...
The neutron scattering facilities worldwide constantly replace or upgrade their instrumental suite to provide the scientific community with unprecedented capabilities. Progresses all-along a neutron scattering beamline, from the improved production and optics to more sensitive detectors, allow nowadays experiments which were unthinkable until some time ago. However, not less relevant are the...
Since 2017, CROSS D-Lab has been developing and operating equipments for J-PARC users to perform chemical deuteration and analysis of D-labeled molecules. So far, aromatic compounds, ionic liquids, and other organic molecules have been deuterated using heterogeneous platinum-group catalysts under hydrogen gas-free conditions, and these molecules have been used in neutron experiments at J-PARC...
The neutron spin-echo system on the Larmor instrument at ISIS has now been operating for more than 5 years. The system was design by TU-Delft to be highly flexible for utilisation in a wide range of Larmor precession techniques including SESANS, SEMSANS, MIEZE-SANS, Larmor Diffraction and TOFLAR. The flexibility and complexity of the system has unfortunately led to some difficulties in routine...
D16 is one of ILL’s 2-axis cold neutron diffractometer. In terms of Q-space and Q-resolution, D16 nicely fills the gap between the small angle instruments and classical diffractometers.
Because of its special characteristics, D16 remains unequaled for the study of a wide range of systems in biology, physics, and material science.
Its specifications have been optimized for the study of...
Chromium arsenide (CrAs) is considered a model system in which superconductivity and helimagnetism coexist. The superconductivity is induced by pressure and forms a dome-like phase region with a maximum TC of 2.2 K at about 1 GPa. The superconductivity occurs in the vicinity of an antiferromagnetical phase of CrAs which is incommensurate and described as a double helix in the literature. This...
The structure and dynamics of materials can be studied on the atomic level with neutron and X-ray scattering experiments as well as molecular dynamics (MD) simulations. We connect experimental data with MD simulations to further enhance the simulations and obtain forcefields that are able to reproduce the measured structure and dynamics.
On the example of water, we establish a workflow of...
The present work focuses on the unique ability of magnetic small-angle neutron scattering (SANS) to quantitatively analyze the magnetic interactions, namely the exchange-stiffness constant and the strength and spatial structure of the magnetic anisotropy and magnetostatic fields in (Fe0.7Ni0.3)86B14 alloy [1]. This particular compound is a promising...
We revisit the antiferromagnetic structure of $\rm Tb_{14}Ag_{51}$ with the propagation vector [1/3,1/3,0] and parent space group P6/m using both magnetic symmetry and irreducible representation arguments. We have found a new magnetic structure under the hexagonal Shubnikov magnetic space group P-6′, which fits much better the experimental data. This new solution was obtained by constraining...
The treatment of water for potable use is one of the great challenges of our time. Reverse osmosis (RO) desalination is a widely used technology for the treatment of sea and wastewater. A main problem is scaling and fouling of the membrane surface, which prevents the optimal use of this technology [1]. Our goal is to investigate these phenomena at the microscopic level using operando SANS...
The first industrial revolution enabled mass production by using steam power in the late 18th century. Progress continued by adding electricity and programmable logic controllers in the second and third industrial revolution, respectively. All this two-century progress was more-less irrelevant for science since progress there requires constant changes and our invention. We are now on the...
In recent years many studies into green solvents have been undertaken and deep eutectic solvents (DES) have emerged as environmentally friendly alternatives in many fields, such as separation processes, metal processing, biocatalysis and electrochemistry.[1] DES are solvents obtained through the complexation of organic compounds, where the interaction between the precursors promotes a...
Polarisation analysis (PA) has been growing in popularity to separate the coherent and incoherent scattering contributions in complex systems. For quasielastic spectroscopy, PA has been used with neutron spin-echo, triple axis, and direct geometry time of flight spectrometers. However, crystal analyser backscattering instruments are the workhorses of quasielastic neutron scattering (QENS), due...
In recent years, the development of high-current accelerator-based neutron sources (HiCANS) has gained in interest to propose a novel option for the next generation of neutron sources. In HiCANS high neutron yields are achieved by irradiating metal targets with proton beams with energies in the MeV range bellow the spallation threshold and currents of several tens of milliamps. Based on this...
The field of Neutron Scattering relies heavily on computer simulations for design of our instruments. Simulations can however be used in a broader scope, including preparation of beamtimes, training and understanding of spurions. To realize this broader scope, simulation packages must be able to include the details necessary to describe the experiment, run sufficiently fast and be easy to use....
Data reduction is a crucial prerequisite to data analysis in neutron scattering expermients; in the case of single crystal diffraction, it involves the reduction of a set of detector images at fixed sample rotation increments to a set of miller indices with integrated intensities. However, the only avaailable mature software solutions are either legacy codes, converted from X-ray diffraction,...
The coupling of spin, charge and lattice degrees of freedom results in the emergence of novel states of matter across many classes of strongly correlated electron materials, ranging from unconventional superconductivity to skyrmions, multiferroicity, materials with a giant magnetoresistance, or hidden order states. Although, the importance of coupled degrees of freedom is widely appreciated,...
Skyrmions are topologically non-trivial spin textures that exhibit an exceptionally efficient coupling to spin currents, notably spin-polarized charge currents and magnon currents as observed in MnSi, FeGe, and Cu2OSeO3 [1, 2, 3]. This raises the question for the microscopic mechanisms that control the pinning of the skyrmion lattice, and how they depend on the topology, electronic structure,...
Transition metal ion compounds that have an orbital degree of freedom have recently been the focus of much attention owing to the importance that spin-orbit coupling plays in the creation of new phases and excitations. We will outline a series of scattering studies illustrating the role that neutrons have in characterizing spin-orbit physics in transition metal compounds. Particular focus...
MLZ successfully operates the two neutron imaging beam lines NECTAR and ANTARES. NECTAR provides fast fission neutrons, thermal neutrons and gammas, which can be combined for multi-modal characterization of larger samples with spatial resolution down to ~100 µm. ANTARES offers a spectrum with a thermal maximum, extended towards cold neutrons, providing higher sensitivity and spatial...
A multitude of structural biology techniques, including crystallography, NMR and cryo-EM, as well as single molecule experiments, have recently provided new and exciting mechanistic insight into protein substrate degradation by AAA+ ATPases and the proteasome. However, direct structural information on the conformational changes of the working complex and on the respective substrate state(s)...
Protein nanoparticles can outperform polymer nanoparticles due to their versatility, biodegradability and low immunogenicity. We have exploited our previous experience in the preparation and characterization of synthetic unimolecular single-chain nanoparticles (SCNPs) to synthesize polypeptide SCNPs based on proteins. The conformational changes due to chain folding or collapse, i.e, an...
This study aims to investigate the changes in superconducting current flow induced by a trapped magnetic field. This is done by using polarized neutrons to image both the trapped magnetic field and the screening field induced by the current flow.
The experiment was conducted at the J-PARC RADEN facility on a multifilamentary YBCO superconductor [1] with a 1T field applied along the current...
Sugar-based surfactants are recognized as green surfactants and widely used in various applications ranged from viscosity modifier to pharmaceutical applications. However, only a scarce number of examples were reported to exhibit non-Newtonian rheological behaviour, and equally underexplored is the strategy to fine-tune the rheological profile. Our recent study shed light on this area by...
From all possible Additive Manufacture methods, the electron beam melting (EBM) of Ti-6Al-4V has the closest properties to the traditionally produced Ti-6Al-4V. Therefore, EBM Ti-6Al-4V can be used in many engineering parts, yet its material properties must be understood completely. In particular, the differences among properties of objects oriented vertically or horizontally with respect to...
ISIS is continually updating and developing its suite of neutron and muon instrumentation in order to respond to the needs of the science community and to ensure ISIS remains a world-leading facility. Currently ISIS is embarking on a large programme called ‘Endeavour’ which aims to deliver 9 major instrumentation projects over a ten year time scale to meet current and future challenges in...
The European Low Energy accelerator-based Neutron facilities Association (ELENA – www.ELENA-neutron.eu) is promoting the development of Compact Accelerator-driven Neutron Sources (CANS) and High Current Accelerator-driven Neutron Sources (HiCANS) in Europe. It represents 7 projects and 8 institutions from major European countries: Italy, Spain, France, Germany, Norway, Sweden, Hungary and...
The European Spallation Source (ESS) is Europe's answer in the continuous strive for the production of neutron beams of ever higher brilliance. The scientific instruments exploiting these beams are an indispensable tool for studying matter and material properties, which will unlock new discoveries from the very fundamental to the highly applicable. The concept underlying the ESS combines a...
Aiming for highest neutron peak brightness, limits are set by the capabilities of heat removal and for pulsed sources even more by the instantaneous power impact. In this respect, the long pulse ESS is still below its limits and has a high potential to boost its performance. Considering the current ESS, the goal should be a compression of proton pulses near to 50 to 100 µs, comparable to the...
With very few large-scale facilities left to serve a leading community of about 5000 European neutron users in the 2030s, the European neutron ecosystem will become extremely vulnerable and capacity-limited. Neutron research in Europe risks losing its strength and diversity if limited access to neutron beam time makes it extremely difficult to maintain a sustainable research program based on...
High-current accelerator-driven neutron sources (HiCANS) [2] claim to cover the gap of neutron production in Europe created by the shutdown of research reactors. The ARGITU project is one of these initiatives to build a regional neutron source in the Basque Country area (Spain).
In this work, a view of the proposed facility focused on accelerator and target will be given. The accelerator is...
The research neutron source Heinz Maier-Leibnitz (FRM II) is a central scientific institute of the Technical University of Munich (TUM) located at the Research Campus in Garching. The FRM II came into user operation in April 29, 2005 and provides neutrons for science, industry and medicine in up to four cycles of 60 days a year. The Heinz Maier-Leibnitz Zentrum (MLZ), a cooperation TUM and...
The role of Liquid-liquid phase separation (LLPS) in biology is increasingly recognised. Here we study two different cases in which LLPS occurs. First, actin remodelling has been found to involve LLPS, which likely acts to upregulate critical proteins and adjust their activity. Preliminary data indicates that cell membrane stiffness is a key factor in coacervation at the cell membrane. The...
The thermal moderator is the key component in a research neutron source to convert the primary neutrons which typically have energies in the MeV regime into useful neutrons for investigations that shall have energies well below 1 eV. In the case of a HiCANS as HBS, the thermal moderator has to be optimized according to the compact target size and to the proton pulse lengths at the different...
The fusion of viral and host cell membranes is a pivotal step in the infection and life cycle of any virus. Despite the massive global research interest in SARS-CoV-2 many aspects of the fusion process are still only rudimentarily understood. Biological fusion assays are widely applied to study different steps of viral-host membrane fusion, however, multidisciplinary approaches offer a broader...
The European landscape of neutron facilities is evolving quickly with the closure of a number of aging research reactors: for example the reactor Orphée in France, BER in Berlin and Kjeller in Norway closed in 2019. While the European Spallation Source (ESS) should start later in this decade, its capacity will not be sufficient to replace the closed facilities. Hence, the Laboratoire Léon...
Carbide-derived carbons (CDC) are porous carbon materials with widely different properties like pore size distribution or graphitization [1]. In this study, quasi-elastic neutron scattering method was used to investigate the hydrogen diffusion in the well-defined pores of three distinct CDC materials [2]. Namely, the predominant shape of pores of the studied CDCs had been shown to be different...
Experiments with very slow – so-called ultracold – neutrons are a powerful probe of models of the early universe at the precision frontier. Flagship experiments with ultra-cold neutrons measure the lifetime of the free neutron and search for its electric dipole moment.
Ultracold neutrons are as well excellent objects to test gravity at short distances, as they are electrically neutral, only...
The removal of water from biological tissue by desiccation or freezing is associated with dramatic changes to membrane structure, often leading to cellular (and organismal) death. We now understand that much of the damage to under these conditions is physical, rather than biochemical. The maintenance of membrane structure is vital for cellular function, but these structures can be affected by...
Quantum materials are a broad class of systems that exhibit many unusual and exotic phenomena [1] in which the chemical and magnetic ground states can be deeply intertwined. For example, ZnV2O4 is an S = 1, cubic spinel which contains a geometrically frustrated pyrochlore sublattice. Previous studies have shown that the magnetic ground state for ZnV2O4 appears to be highly sample dependent,...
Quantum matter is characterised by competing and intertwined orders. Here I will present our recent advances in using uniaxial pressure as a clean “surgical” tool to tune quantum phases while simultaneously obtaining microscopic insights via scattering experiments. In particular, we address two directions - minimizing the background and enabling the tuning in-situ.
First, we study spin...
In the last years, superconductivity has been observed in a couple of iron based one dimensional compounds, BaFe$_3$X$_3$ X=S,Se. Indeed, for both compounds, a pressure induced superconducting dome develops above 10 GPa and below 14 K. A significant difference between the two systems is their magnetic ground state at low pressure. The magnetic order of BaFe$_3$Se$_3$ takes the form of...
This work is focused on atomistic molecular dynamics (MD) simulations of water carried out at 300 K. The main goal was to better understand the experimental results of the coherent dynamic structure factor S(Q,$\nu$) of D$_2$O that were obtained by means of neutron scattering with polarization analysis and previously reported by us [1]. First, the simulations were directly validated by direct...
The Heinz Maier-Leibnitz Zentrum (MLZ) operates at Germany’s sole neutron source FRM II the diffractometer STRESS-SPEC optimised for fast strain mapping and texture analyses. The STRESS-SPEC group was the first to pioneer sample handling and positioning via industrial robots at neutron diffractometers [1, 2]. However, the current robot is limited in its use due to insufficient absolute...
Atmospheric aerosol particles can be coated with organic materials, impacting aerosol atmospheric lifetime and urban air quality. Coatings of organic materials are also found on indoor surfaces such as window glass. Oleic acid is a fatty acid surfactant that is abundant in cooking and marine aerosol emissions. Under ambient conditions it can self-assemble into lamellar bilayers (stacks) with...
The atomic-scale structure of liquids and glasses is crucial for understanding their material properties. However, amorphous materials lack of translational periodicity that leads to the Bragg peaks observed in the diffraction pattern for a crystal. Instead, the diffraction pattern is diffuse, and it is a challenge to solve the structure. The understanding of the neutron diffraction patterns...
Over thirty years ago, the high-temperature cuprate superconductors were discovered, and although many of the phenomenological tools developed to describe superconductivity could still be applied, the Bardeen-Cooper-Schrieffer (BCS) theory for superconductors was found not to work. It became clear that a Cooper pair of electrons formed, but that the superconducting energy gap had become more...
5 min intro, 30 min talk by the awardee, 5 min q&a
Neutron interferometry [1], where an interference effects of matter waves passing through a perfect silicon-crystal interferometer is observed, has established a powerful tool for investigation of fundamental quantum mechanical concepts with massive particles [2]. In this talk I will give an overview of our recent work on weak measurements [3], a new type of quantum variable introduced by...
We have developed the concept of a new type of a 120º wide-angle polarisation analyser and report first results of the prototype. The analyser is based on the principle of internal reflections of magnetic FeSi multilayers in straight, 150 µm thin Si channels. This internal reflection avoids the SLD step present between air. This technique yields high transmission and produces no blind spots on...
In order to provide our users the possibility to complete their neutron scattering data with real space images we will present the Electron Microscopy possibilities at MLZ consisting of a Cryogenic transmission electron microscope Cryo-TEM (JCNS) and an Environmental Scanning Electron Microscope ESEM (JCNS & Hereon).
TEM yield real space images of soft matter systems, particularly in...
Many modern high performance alloys feature ferromagnetic elements like Co or Ni. With SANS being a principal technique to investigate the nanostructure of these compounds in in-situ conditions, the
ever present magnetic scattering can be of similar magnitude as the nuclear signal. Magnetic fields combined with high temperatures can hence be a key ingredient for studies of Co or Ni based...
Heterocyclic amines, such as piperidine and N-methylpiperidine aggregate in aqueous solutions due to hydrogen bonds between hydration water molecules. No such aggregation occurs in the mixtures of these amines with other hydrogen-bonded solvents, such as methanol or ethanol. This difference highlights the active role of water solvent in promoting the self-aggregation. However, the role of...
Amphiphilic diblock copolymers feature self-assembly behavior in aqueous solution. In particular, poly(methyl methacrylate)-b-poly(N-isopropylacrylamide) (PMMA-b-PNIPAM) forms core-shell micelles upon heating above the cloud point of PNIPAM (Tcp) [1]. Previously, it was found that pressure strongly affects the dehydration extent of PNIPAM homopolymers in aqueous solution [2].
Here, we present...
The scientific case of the FREIA instrument at ESS is partly based on the measurement of reflectivity with very fast time-resolution. The novel elliptical guide design delivers up to 3 collimated beams onto the sample position and thereby enables the possibility of quickly changing the incidence angle without moving the sample. However, it remains technically challenging to achieve sequential...
The 3He group has developed in-situ polarizers for many JCNS instruments including MARIA, TOPAS, KWS1, POLI, and KWS2 and will provide another two polarizers for the ESS for DREAM and TREX. We develop all 3He cells and magnetic systems in house, as well as the laser sources for the FRM2-based devices. We have also work towards wide angle analysis with C-shaped analyzer cell. The status and...
Polarized neutron imaging (PNI) uses Larmor spin precession to spatially resolve bulk magnetic properties [1]. In recent years, it has been advanced with applications like visualizing magnetic domains [2] or vector-fields [3].
Grain oriented silicon steels, which are used as magnetic core material, have grains and magnetic domains in the mm to cm range and a preferential magnetization axis....
Following the successful guide upgrade at SINQ [1], PSI continues to improve the instrumentation to take advantage of the performance gain. The resulting boost in signal to noise enables faster data aquisition and allows more demanding experiments.
This could be experiments allowing for smaller samples sizes, at extreme conditions, with increased complexity or combinations of all three....
Antibodies play a crucial role in the immune response of mammals. Monoclonal antibodies (mAbs) are particularly relevant for therapeutics due to their high specificity and versatility. The pharmaceutical challenge is to formulate highly concentrated mAb solutions to achieve a significant therapeutic effect, while keeping their viscosity below the subcutaneous injectability limit [1], thus...
Quasi-elastic neutron scattering (QENS) allows to probe with a high energy resolution the total scattering function as a function of energy and momentum transfer $\hbar\omega$ and $q$, respectively. Classical QENS spectra are often captured with quasi-continuous energy transfers with acquisition times of several hours. Since the spectrometers are constantly upgraded, new measurement techniques...
The time-of-flight engineering diffractometer BEER [1], which is under construction at the European Spallation Source (ESS), will offer new opportunities for investigations of engineering materials and components using a multi-scale approach and under near-processing conditions.
BEER combines the high brilliance of the ESS source with large instrument flexibility. The diffractometer includes...
G-quadruplexes (G4s) formed by the human telomeric sequence AG3(TTAG3)3 (Tel22) play a key role in cancer and ageing. G4 structures are known to display a variety of topologies, which are determined by several factors, resulting in structural polymorphism. Neutron Scattering techniques are a valuable tool to investigate how G4 structural polymorphism and ligand binding affect their...
The annual global cost of friction and wear is estimated to be €2.5 trillion and represents a significant energy loss. Organic friction modifiers (OFMs) are amphiphilic surfactants utilised to minimise engine losses with the aim of enhancing vehicle fuel economy. Conventionally, OFMs are thought to adsorb at metallic surfaces forming compact monolayer surface films. These reduce friction by...
Ni/Ti is the material system of choice for non-polarizing reflective multilayer neutron optics such as monochromators, wave guides, and focusing devices. The reflected intensity as well as neutron energy range from state-of-the-art multilayers are hampered by an interface width limiting the optical contrast. Our previous work has shown that incorporation of low-neutron-absorbing 11B4C gives...
It is known [1] that optimized low-dimensional liquid para-H2 moderators can deliver 2-3 times higher cold neutron brightness compared to volumetric para-H2 moderators.
We present a new analytic approach to calculate the brightness of liquid para-H2 moderators. It is shown that the brightness gain is the near-the-surface effect, so that narrow cold moderators shaped as elongated...
Incorporation of organic molecules into the lattice of inorganic crystalline hosts is a common phenomenon in biomineralization and is shown to alter various properties of the crystalline host. Recently, we manipulated magnetism in MnCO$_3$ by admitting a specific single amino acid into its lattice matrix. Bulk measurements showed a clear negative (positive) correlation between amount of...
10B-based solid-state neutron detectors are a viable replacement to 3He detectors. Neutron irradiation of 10B produce charged detectable ions of 4He and 7Li. The detector efficiency using a planar thin film neutron converter configuration is limited by self-absorption of the conversion products in the layer. A 3D configuration, which allows for the conversion products to exit the converter,...
A dedicated test beamline (TBL) is being built to provision the commissioning of the ESS spallation source. The functionality of the beamline employs “camera obscura” principle, which allows to observe both thermal and cold neutrons emitted from different parts of the so-called butterfly moderator. The layout of TBL simply consists of a tapered collimator and a changeable pinhole with...
We present recent developments in the field of innovative neutron optics using perfect Silicon single crystals.
A multiplexed array prototype analyzer has been constructed for the cold neutron triple axis spectrometer ThALES. The prototype consists in an array of 17 Si stacks of 2 mm of thickness. Each stack is composed of 2 plastically bent Si(111) blades with a bending radius of 2 m. The...
The study of condensed matter is often achieved by perturbing the system thus creating a resultant change in material properties that provides an insight into the atomic scale interactions. One such perturbation is pressure. Pressure offers a convenient way to perturb quantum spin liquids and tune quantum phase transitions by altering the atomic positions and thereby the dipolar interactions...
One of the most promising use cases of magnetic hyperthermia, is the use of magnetic nanoparticles (MNPs) for cancer therapy. In this treatment, MNPs are immersed into tumours and by heating with external magnetic fields, typically 100-900 kHz, destroy cancer cells. Since it is a clinical application the optimization of field parameters and in turn, the heating power, is crucial to maintain...
The superADAM reflectometer at the ILL has been recently upgraded with a low takeoff angle extension. The new extension represent a stand alone simplified two axis diffractometer operating at 3.2Å. It is designed with speed in mind and provides faster measurement at higher Q-vectors which would not normally be accessible at a longer wavelength. The basic overview of the instruments...
High-performance instrumentation projects rely on high-performance neutron guide infrastructure. During the extended reactor outage (2021 – 2023) we have replaced the H1-H2 beam-tube, in-pile optics and three new guides with innovative geometries to provide intense neutron beams to new or upgraded instrumentation.
The upgraded IN5 (2019) time-of-flight spectrometer and its new elliptically...
Dioctadecyldimethylammonium bromide (DODAB) show rich phase behaviour at different temperature and concentration [1]. We have studied the effects of Non-steroidal inflammatory drugs (NSAIDs), aspirin (Asp) and indomethacin (Indo), on the phase behaviour and the dynamics of DODAB lipid bilayer using quasielastic neutron scattering techniques (QENS). Elastic window scan showed that Asp and Indo...
We report on a library of models for Quasi Elastic Neutron Scattering (QENS) data. This development, initiated by SINE2020 Workpackage 10 on Data Treatment, was to develop an exhaustive library of dynamical models in order to increase interoperability and modularity for rapid prototyping. Different building blocks are provided to users and can be combined, convoluted and plugged into different...
The influence of the basal texture of the hot-rolled sheet of the AZ31 magnesium alloy on the activity of individual deformation mechanisms and its implication on the mechanical response of the material was studied using a combination of advanced in-situ experimental techniques. Neutron diffraction coupled with acoustic emission (AE) was employed to monitor the twinning activity and the...
Aluminum-alumina composites with interpenetrating network structure are interesting structural materials due to their high resistance to elevated temperature and frictional wear, good heat conductivity, enhanced mechanical strength and fracture toughness. In this paper aluminum-alumina bulk composites and FGMs are manufactured by pressure infiltration of porous alumina preforms with molten...
The cold neutron diffractometer DMC at SINQ, Paul Scherrer Institute, Switzerland, has recently undergone a major upgrade, and I will present the highlights. The cold neutron guide is upgraded, and DMC is now equipped with a large 2D neutron detector. Special features are high detection efficiency, large solid angle coverage and two-dimensional readout. For powder diffraction experiments we...
In La-based cuprates the low superconducting transition temperature is accompanied with having only a partial gaping of the magnetic excitation spectrum [1]. This allows the magnetic excitations of La-based cuprates to be studied to lower energies than in other cuprate materials [1], and are often compared to those of charge-stripe ordered La$_{2-x}$Sr$_{x}$NiO$_{4+\delta}$ [2,3].
Inelastic...
The application of HOPG (highly oriented pyrolytic graphite) as an efficient monochromator and filter material for neutron instrumentation has been discovered more than 50 years ago. Despite the fact that HOPG has been in use for such a long time, there is still room for improvements regarding its implementation in neutron beam optics. The features of a novel concept called POSI...
The use of neutron scattering techniques to understand characteristics of materials at the nanoscale has matured to a point where the subtlest of reciprocal space features can be quantified. In contrast, radiographic imaging using thermal and cold neutrons is entering adolescence, garnering substantial interest by science communities external to traditional scattering disciplines and receiving...
The epsilon phase of Fe$_2$O$_3$ (ε-Fe$_2$O$_3$) presents captivating properties and it is receiving extraordinary attention due to its great application potentials. It stands out for its huge coercive field (up to 2 T at room temperature), millimeter-wave ferromagnetic resonance, remarkable non-linear magneto-optical effect, magneto-electric coupling [1], and room temperature ferroelectricity...
LaCoO$_3$ exhibits two crossovers at T$_{SS} \approx$ 100 K and T$_{MI} \approx$ 500 K observed in various physical properties such as thermal expansion and electric susceptibility. These crossovers are typically associated with the temperature dependent population of excited spin states of the Co$^{3+}$ ion, which evolves upon heating from the low-spin (LS), S = 0, to high-spin (HS), S = 2,...
Spin waves in chiral magnetic materials are strongly influenced by the Dzyaloshinskii-Moriya interaction, resulting in intriguing phenomena like nonreciprocal magnon propagation and magnetochiral dichroism. We studied the nonreciprocal magnon spectrum of the archetypical chiral magnet MnSi and its evolution as a function of magnetic field in all magnetic phases. Using inelastic neutron...
High-temperature superconducting split pair magnet for neutron scattering environment with the metal-as-insulation (MI) winding technique enables mechanical strength with quench risk reduction. Quench protection is crucial for superconducting magnet system's reliable and safe operation. High-temperature superconductors enable a rapid rise to the maximum magnetic field, compressed dimensions,...
In the last two years the neutron optics group of FRM II has successfully sputtered non-depolarizing m=2 Cu/Ti supermirrors, which have been prepared with a standard DC magnetron sputtering facility. Control on the roughness grow and interdiffusion allowed us to get a very good maximum angle of total reflection (ca. 0.21°/λ) and polarized neutron reflectivity above 90%, as measured at the...
The current unsustainable meat consumption makes a growing number of meat consumers turn to plant-based meat alternatives (PBMAs). To facilitate the transition towards a plant-based diet with its health and environmental benefits, the demand for an accurate reproduction of meat-like structure, texture and mouthfeel in PBMAs is pressing. High Moisture Extrusion Cooking (HMEC) is one of the...
ESS/ISIS Support Laboratories – how we best support the neutron scattering users through collaboration
K. Michel, M. Sharp, H. Schneider, M. Hartl
G. Stenning, S. Langham, S. Youngs, M. Jura
Facility Staff involved in supporting neutron scattering users in laboratories during their beamtime need possibilities for scientific and technical exchange, as well as personnel development...
The thermal beamport SR8 at the research neutron source Heinz Maier-Leibnitz in Garching will be optimized to allow the simultaneous operation of three independent monochromatic powder diffractometers. SPODI will continue to be one of the world-leading high-resolution powder diffractometers. FIREPOD will be a dedicated high throughput instrument, well suited for a broad range of fast...
We present the developments and improvements of the SANS-1 instrument, a joint TUM and Hereon project [1] since the first user experiments in 2012. The classical pinhole SANS-1 features now two velocity selectors and an ultra-fast TISANE chopper, efficiently allowing to tune flux, resolution, duty cycle and frame overlap, including time resolved measurements with repetition rates up to 10 kHz....
In 2027, ESS will welcome its first users. To be able to support their experiments, the Materials and Physics Support group has already started to procure and integrate an ambitious list of sample environment systems (SES), from the simplest wet cryostat to the most advanced magnet. In our scope, SES for low and high temperatures, magnetic and electrical fields, high-pressure and...
The UK in-kind contribution to the first 15 instruments at ESS includes small-angle neutron scattering and reflectometry instruments.
As one of two SANS beamlines under construction, LoKI has been designed specifically with the needs of the soft matter, materials, and bio-science communities in mind. For example, its high flux and wide simultaneous Q-range will make it ideal for performing...
In the crystal structure of KDP (КH2PO4) the phosphate tetrahedra are linked together by a net of O-H-O hydrogen bonds. At ambient pressure and temperature protons are disordered in a two-minimum potential along the bonds. At a temperature of 123 K a ferroelectric phase transition takes place related to the locking of protons in one of these two energy minima. We used inelastic neutron...
SKADI [1] is a small-angle neutron scattering instrument being constructed at the European Spallation Source (ESS). This TOF instrument with 20 m collimation and 20 m sample detector distance will cover 3 orders of magnitude in Q-space simulateneously (10$^{-3}$ to 1 Å$^{-1}$), offer polarised scattering, as well as a versatile sample area of 3$\times$3 m $^2$. With a flux of approximately...
We present a MIEZE (Modulation of intensity with zero effort) set-up for high-resolution neutron spectroscopy at momentum transfers up to 3Å$^{-1}$, energy transfers up to ~20meV and an energy resolution in the μeV-range using both thermal and cold neutrons. One prominent advantage of MIEZE compared to classical neutron spin-echo is the possibility to investigate spin-depolarizing samples or...
The small-angle neutron scattering (SANS) diffractometer KWS-2 at the neutron source Heinz Maier-Leibnitz (MLZ, Garching, Germany) is operated by the Jülich center of neutron science (JCNS), with applications focusing on soft matter, colloidal particles, micelles, nanocomposites, and polymer gels. In recent years, we are working on the establishment of a new sample environment – the in-situ...
Mucins and mucin-like molecules[1] are an important group of biomacromolecules characterized by a charged and highly glycosylated linked peptide backbone. The fundamental structural unit is a bottle-brush-like morphology organized into higher level aggregates or networks forming a gel which is resistant to flow. The electrostatic interactions between polymer chains are of interest to...
The high-intensity reflectometer MARIA of JCNS is installed in the neutron guide hall of the FRM-II reactor, and is using a velocity selector (4.5Å<λ<40Å) with a resolution of 10%. By using Fermi-Chopper the wavelength resolution can be increased to 1% or 3%. The beam is polarized by a double-reflecting super mirror (4.5Å<λ<12Å) and in the vertical direction the elliptically focusing neutron...
The hexagonal close packed phase of cobalt (hcp-Co) is associated with numerous stacking faults while the face centered cubic phase of cobalt (fcc-Co) has considerably less stacking faults, as shown e.g. in [1]. Two domains of hcp-Co stacked one above the other with a stacking fault in between are usually delimited by a small interface region of a few fcc-Co layers as shown e.g. in [2,3]. The...
Binary Cu-Ti alloys feature a large, undercooled liquid region and a high glass-forming ability (GFA). Thus, they provide the rare possibility to obtain two component bulk metallic glasses (BMGs), which is mainly addressed to special properties of the Cu-Ti system i.e., in the melt, it features a positive excess volume, whereas it still has a negative enthalpy of mixing.
Although, the...
Pyrolytic graphite (PG) has a high Bragg reflectivity for neutrons and is therefore much used for monochromators and analyzers in all types of backscattering and triple-axis spectrometers (TAS).
PG can also be the source of background signals since it has low velocity phonon branches. If interpreted as Bragg scattering, these phonon branches will appear as broad spurious background signals....
Temperature-induced spin reorientation in orthoferrites (RFeO$_3$) and orthochromites (RCrO$_3$) has recently attracted a lot of attention because of its various potential applications. Spin reorientation in these oxides can be utilized to design functional devices like magnetic switches, magnetic read/write heads, etc.
This work presents the results of spin reorientation and rare-earth...
Hydrogen storage technologies in low weight hydrides promise an aid with the global aim of CO2-emissions reduction. High mass energy densities are needed e.g. for heavy-load long distance mobility like trains, trucks, and airplanes. One of the potential reaction based systems is Mg(NH2)2+LiH with a reversible hydrogen capacity of 5.6 wt.% below 200oC. The kinetics of hydrogen...
We present a newly developed program that combines molecular dynamics (MD) simulations with an optimisation protocol. e.g. using Monte Carlo (MC) methods, in order to determine the force field parameters values that lead to the best agreement with experimental data. The program is currently focussed on classical MD simulations and quasi-elastic neutron scattering (QENS) data, such as dynamic...
The PERC facility is currently under construction at the FRM II in Garching, Germany. It will serve as an intense and clean source of electrons and protons from neutron beta decay for precision studies. It aims to improve the measurements of the properties of weak interaction by one order of magnitude and to search for new physics via new effective couplings.
PERC's central component is a 12...
Polarised neutrons will be a capability offered to users in many ESS instruments. Of the currently approved 15 instruments [1], 12 aim to have the capability [2]. They include 1 imaging instrument, 2 SANS instruments, 2 reflectometers, 3 diffractometers, and 4 spectrometers. In conjunction with in-kind contributions and external grants, the ESS Polarisation Project will support 10 instruments....
Unsaturated molecular crystal can polymerize into extended carbon structure like diamond nanothread and graphene nanoribbon under external pressure, which is called pressure-induced polymerization (PIP). PIP has an obvious topochemical feature, with the structure of the polymeric product similar with the reactant. By analyzing the crystal structures of many reactants, we conclude that alkynes...
The European Spallation Source (ESS), expected to be the world’s most powerful neutron source, is currently under construction in Lund. Among the endorsed instruments foreseen for day one instrumentation at ESS, is the cold time-of-flight spectrometer CSPEC [1]. CSPEC is a joint proposal from the Technische Universität München (TUM), Germany, and the Laboratoire Léon Brillouin (LLB), Saclay,...
Huntington’s Disease (HD) is a genetically inheritable neurodegenerative disorder caused by a mutation in the gene encoding the protein Huntingtin (Htt). The mutation causes an increase in CAG trinucleotides in the first exon, which increases the number of glutamines in the poly-glutamine (Poly-Q) tract of the intrinsically disordered N-terminal region of the protein. HD symptoms only manifest...
The mineral jarosite KFe3(OH)6(SO4)2 is a frustrated antiferromagnet. It exhibits long range magnetic order (LRO), when cooled below TN = 60 K, due to DM interaction. The mineral is a classic example of a 2D geometric frustration Kagome lattice. It has earlier been discovered that a substitution of H3O or D3O for K on the A-site prevents LRO. Instead, a spin glass transition sets in at Tg =...
Single-Chain NanoParticles (SCNPs) are nano-objects obtained by intra-molecular cross-linking of individual macromolecular chains (‘precursors’). Due to their ultra-small size, softness and internal compartmentalization, they are good candidates for nanotechnology, e.g., for SCNPs was to form part of all-polymer nanocomposites (NC), i. e., mixtures where such nanoparticles are dispersed in a...
Hydrogels are at the forefront of scientific attention especially in the biological and biomedical fields providing the basis for stimuli-responsive artificial tissues etc. We study physically crosslinked hydrogels based on ionenes, positively charged polymer chains, for which strong counterion-specific effects have been observed previously [1]. The nature of the ionene counterion modifies...
The D16 instrument is a versatile cold-neutron diffractometer operating at the ILL. It benefited from a number of upgrades over the years, such as the installation of a large-area 3He Multi-Wires Proportional Chamber (MWPC) in 2014. This detector provides a resolution of 1 x 1 mm2 over an area of 32 x 32 cm2. After 8 years of operation, the detector is now being replaced by a new curved...
We report on the results of inelastic neutron scattering (INS) of KCu$_4$P$_3$O$_{12}$. Cu$^{2+}$ ions carry $S = 1/2$ spins. Four types of nearest-neighbor exchange interactions form the eight-spin zigzag-chain ($J_1 - J_2 - J_3 - J_4 - J_3 - J_2 - J_1$ chain). We evaluated the exchange interactions as $J_1 = -8.5$ meV (antiferromagnetic), $J_2 = -2.7$ meV, $J_3 = -3.9$ meV, and $J_4 = 6.2$...
Grazing incidence small angle neutron scattering (GISANS) has the potential to reveal highly relevant scientific questions in many areas of science. Examples include biomembranes, responsiveness of lipid membranes to external stimuli in situ such as exposure to light for photolipids and hydration, in-plane structure of DNA composites and micellar nanoreactors. These experiments are often...
The HEiDi single crystal diffractometer at the hot source of the MLZ's FRM II offers high thermal and hot flow, high resolution and a large Q range. These properties make it an excellent tool to obtain detailed structural information for a wide range of current scientific topics.
Within the framework of two recent projects funded by the BMBF, great efforts have been made to expand the...
The antisymmetric Dzyaloshinskii-Moriya interaction (DMI) plays a decisive role for the stabilization and control of chirality of skyrmion textures in various magnetic systems exhibiting a noncentrosymmetric crystal structure. A less studied aspect of the DMI is that this interaction is believed to be operative in the vicinity of lattice imperfections in crystalline magnetic materials, due to...
The heteroaggregation between azo dyes and surfactants is an interesting phenomenon. The responsivity of the dye spectrum to changes in their chemical environment is often used to monitor alterations in a solution state by means of UV/vis-spectroscopy. However, little attention was paid to the morphology of dye/surfactant assemblies. Small-angle neutron scattering (SANS) with contrast...
To investigate superalloys under application conditions, which are often a combination of very high tensile loads, and temperatures in oxidizing environments, a new testing machine has been developed for use at several neutron instruments at the FRM II. The testing machine is designed to investigate the material behavior up to 100 kN. Different specimen grips were developed to perform tensile,...
Propagation-based phase contrast imaging is an established method in X-ray imaging. Recent results show that this approach with a Paganin type filter [1],[2] increases neutron image contrast significantly. We demonstrate that we can use this to distinguish materials with low neutron absorption. The neutron experiments were performed at BOA (SINQ@PSI [3]) using the neutron microscope [4]. These...
CAMEA (Continuous Angle Multiple Energy Analysis) is a novel crystal analyzer concept optimized for neutron detection efficiency in the horizontal scattering plane [1]. The design comprises consecutive, upward scattering analyzer arcs set to analyze different neutron energies and an array of position sensitive detectors. CAMEA enables rapid mapping of excitations and is in particular...
Modern neutron Multi-Wire-Proportional-Chambers (MWPC) operating with $^{10}$B$_{4}$C films as solid-state-converter can surpass the performance of ones based on $^{3}$He in terms of position resolution and count rate capability at similar detection efficiency [1,2]. The use of large area coated converters on thin foils forces to develop a mechanical concept to avoid deformations of the...
Powder Bed Fusion, especially Selective Laser Melting (SLM), has gained high acclaim among material engineers in the recent years since it brings a new possibility of production of engineering components with complex shapes. Additionally, by further rotary swaging, the mechanical properties of the components can be enhanced alongside the reduction of some characteristic defects of the SLM...
The NMX Macromolecular Diffractometer is optimised for small samples and large unit cells dedicated to the structure determination of biological macromolecules by crystallography. Neutron macromolecular crystallography is mainly driven by its ability to locate hydrogen atoms in biological macromolecules. NMX is a macromolecular diffractometer that uses the time-of-flight (TOF) quasi-Laue...
We present the rare existence of d5 off-centering induced weak ferroelectric polarization and demonstrate its correlation with observed magnetoelectric (ME) properties in the G type (TN~210 K) antiferromagnet Fe2TeO6 compound.
PUMA is the thermal neutron three-axes spectrometer (TAS) at MLZ. Owing to the dynamical double-focusing technique and compact neutron optics with wide beam divergence, PUMA is mainly characterized as one of the highest neutron flux TAS. In addition, PUMA is equipped with the early generation multi-analyzer and -detector setup, which is suitable for a type of time-dependent kinetic...
The biological functionality and structure of DNA and RNA,[1] as well as the activity of various nucleoside-processing enzymes,[2] are all deeply linked to the properties of the underlying five-membered ring sugars, particularly furanosides. The study of five-membered rings is more challenging because of the strain of the ring in all conformations which leads to a small energy difference...
Physical properties of nanoclusters, nanostructures and self-assembled nanodots, which in turn are concomitantly dependent upon the morphological properties, can be modulated for functional purposes. Here, in this article, magnetic nanodots of Fe on semiconductor TiO2 nanotubes (TNTs) are investigated with time-of-flight grazing incidence small-angle neutron scattering (TOF-GISANS) as a...
Oxygen ion conductors are materials of major interest for a series of application in the area of solid state ionics. In particular, oxides with brownmillerite type structure (A2BB’O5) have attracted much attention, showing oxygen ion mobility down to ambient temperature.
Brownmillerite type frameworks containing B-cations with saturated or empty electron shells (d0 or d10 configurations)...
MIRACLES is the neutron backscattering spectrometer of the European Spallation Source [1]. The instrument will display a flexible tuning of the energy resolution, that allows exploration of a broad range of timescales, from the nanosecond to the picosecond, along with an unprecedented wide dynamic range and a versatile selection of energies for quasielastic and inelastic scattering experiments...
Proton-conducting oxides are an important class of materials for next-generation, intermediate-temperature solid-state electrolytes in e.g., proton conducting fuel cells. While most development efforts have been directed toward materials exhibiting the cubic perovskite structure, in recent years several promising alternative structures have emerged. One of these is the pseudo-cubic structure...
Stimuli responsive materials, which can self-assemble depending on the environment, are of great interest. In this context nanoparticles offer unique opportunities as they can be custom designed and it is very important to understand the assembly mechanisms to control the resulting structures, which is crucial for the synthesis of materials with controllable properties. It is well known, that...
The monochromatic neutron filed generated by $^{3}$H($^{2}$H,n)$^{4}$He reactions is typically used in fusion-related experiments. mainly devoted to material damaging, plasma diagnostics development and cross sections measruements. As a matter of fact, the monochromatic 14 MeV neutrons can be slowed down to obtain thermalised neutrons with the typical spectrum of a spallation neutron source,...
Thermal density fluctuations of supercritical CO$_{2}$ have been studied using small-angle neutron scattering (SANS), whose amplitude (susceptibility) and correlation length show the expected maximum at the Widom line. At low pressure, the susceptibility is in excellent agreement with the values determined from the mass density. Surprisingly, droplets form between 20 and 60 bar above the Widom...
In many applications like in biomedicine, ferrofluids, or heterogeneous catalysis, iron oxide nanoparticles (IONPs) feature a solid-liquid interface with the wetting water molecules. The interfacial properties including dynamics play an important role, yet have been barely addressed so far. Quasielastic neutron scattering (QENS) can access the dynamics of water molecules at the surface of...
First discovered in 1992, RAlGe (R –rare earth metal) was reported initially to crystallize in the so-called ThSi2 structure-type with a centrosymmetric space group I41/amd (No. 141) [1]. Later on, it has been realized instead that RAlGe crystallizes in the LaPtSi-type structure [2,3] with a body-centered space group I41md (No. 109). From recent first principle theoretical calculations, it has...
JCNS at MLZ offers the opportunity for thin film fabrication in combination with neutron investigation proposals utilizing a Molecular Beam Epitaxy (MBE) setup on site.
The design of the MBE setup will be presented revealing its versatility with respect to the fabrication of different material compositions of thin films like “classical” magnetic thin films, transition metal oxide...
KWS-2 is a classical small angle neutron diffractometer where the pinhole mode with different neutron-wavelengths and detector distances can be combined with focusing mode with MgF$_2$ lenses to reach a wide Q-range between 2x10$^{-4}$ and 1.0 Å$^{-1}$. Upgrades of the detection system and sample environment are currently in progress. A wide-angle detection option is currently being tested and...
Stimuli responsive polymers have gained much attention due to their unique properties. If polymer thin films exhibit a reversible volume change upon exposure to external stimuli such as temperature, pH, or solvents, they become promising candidates for applications such as nanoswitches or sensors. Polymers like poly(N-isopropyl methacrylamide) (PNIPMAM), which are sensitive to two stimuli can...
VITESS [1] is a Monte Carlo based simulation package for neutron ray-tracing now hosted by the Forschungszentrum Jülich. We show the VITESS simulation results of the KWS-I Small Angle Neutron Scattering (SANS) instrument at the FRM-II research reactor and compare them with experimental measurements. With the instrument correctly simulated, it is possible to generate a synthetic database of...
The search for renewable and sustainable electrical energy storage devices has become vital to meet current environmental challenges [1]. Iron oxides represent a promising,environmentally friendly material [2,3] which can be converted into a lithium intercalating material via chemical lithiation [4]. Owing to their high surface area and thus potential high electrochemical surface activity,...
$SrTiO_3$ is an incipient ferroelectric material with a large static dielectric response, which shows notable phonon anomalies and electrostrictive response (PRB 62, 13942). It is also a neutron triple-axis classic, with seminal work by Cowley, Shirane in which they show the application of available phonon theories and sixties neutron scattering methods.
First principles calculations of...
Magnetic nanoparticles (NPs) are technologically relevant for catalysis, high density magnetic data storage, ferrofluids and medical applications. A drastically reduced magnetization compared to the bulk material is commonly attributed to spin disorder in magnetic NPs. Such spin disorder has recently been suggested to be beneficial for magnetic heating, e.g. in intracellular magnetic...
Almost a century ago, in 1931, Bethe provided an ansatz to find the exact eigenvalues and eigenvectors of the spin-1/2 Heisenberg Hamiltonian with antiferromagnetic nearest-neighbor interactions. In zero field, the ground state is a singlet, and the inelastic neutron spectrum is a continuum of pairs of topological excitations called spinons. In an applied magnetic field, longitudinal and...
The European Spallation Source, currently under construction in Lund, Sweden, will originally make available a suite of 15 state-of-the-art neutron scattering instruments, which will be served by a high-brightness moderator placed above the spallation target. The current infrastructure of ESS, however, allows for a second, alternative moderator to be constructed and positioned below the...
Diffraction is a key tool for structure analysis. However, currently available software for modelling and analysis of diffraction data may be, on the one hand, difficult for new users looking to apply diffraction to their field of expertise and, on the other hand, not flexible enough for domain experts.
EasyDiffraction [1] aims to lower the barrier of entry to diffraction data analysis by...
The cold neutron three-axis spectrometer IN12 is operated by the Juelich Centre for Neutron Science (JCNS) in collaboration with the CEA-Grenoble as a CRG-B instrument at the Institut Laue-Langevin (ILL) in Grenoble, France.
With an upgrade accomplished in 2012 the instrument has been relocated to an end position of a new guide and the whole primary spectrometer has been upgraded.
With a...
MLZ successfully operates the two neutron imaging beam lines NECTAR and ANTARES. NECTAR provides fast fission neutrons, thermal neutrons and gammas, which can be combined for multi-modal characterization of larger samples with spatial resolution down to ~100 µm. ANTARES offers a spectrum with a thermal maximum, extended towards cold neutrons, providing higher sensitivity and spatial...
Attenuation-based radiography and tomography (CT) are well-established experimental techniques for non-destructive visualisation of the object interior, where X-/gamma-rays and neutrons are most commonly used types of the incident radiation, but also protons or heavy particles (e.g. ions) can be used as a source. Different radiation sources are used along with phase-contrast, Bragg and/or...
It is well known that beyond a certain size magnetic nanoparticles exhibit a nonuniform internal spin structure. This feature, which is of relevance for many problems of practical interest (e.g., biomedical imaging and drug delivery), is commonly ignored when it comes to the analysis of magnetic neutron scattering data on nanoparticle ensembles. By means of numerical micromagnetic computations...
The cold triple-axis spectrometer (TAS) FLEXX at HZB is a well-designed and upgraded instrument [1-4]. There is a strong wish that this excellent instrument should be preserved for the community after the shutdown of the HZB neutron source. One attractive gap in the present instrumentation suite of MLZ, is the Larmor-diffraction technique [5-6] (LD) and, as a natural extension, cold neutron...
Myelin basic protein (MBP) is intrinsically disordered in solution and is considered as a conformationally flexible biomacromolecule. Here, we present a study on perturbation of MBP structure and dynamics by the denaturant guanidinium chloride (GndCl) using small-angle scattering and neutron spin–echo spectroscopy (NSE). A concentration of 0.2 M GndCl causes charge screening in MBP resulting...
We present neutron scattering data on the hexagonal rare-earth diboride ErB$_2$. ErB$_2$ orders magnetically below $T_c$ = 14 K, where the magnetocrystalline anisotropy exhibits strong easy-plane characteristics, as established from measurements of the specific heat, ac susceptibility, magnetisation, and electrical transport. In order to investigate the magnetic structure we performed neutron...
The magnetoelastic coupling between phonons and f-electron transitions in crystal electric field (CEF) has been of interest for long time already but still lacks a systematic understanding. It was first recognized in 1980s in CeAl2 that showed an unexpected excitation spectrum. It was explained by a qualitative theory developed by Thalmaier and Fulde [2] but limited to this case. Such...
Elemental analysis based on neutron activation provides a number of advantages for the study of ancient objects. It is non-destructive, the sample preparation is simple, and most elements can be analyzed with low detection limits. The most commonly used methods are prompt gamma activation analysis (PGAA) and instrumental neutron activation analysis (INAA), which enable a panoramic bulk...
Mushroom is a concept of an indirect neutron spectrometer with a secondary spectrometer based on a super flat-cone analyser made of highly oriented pyrolytic graphite with an array of position-sensitive detectors (PSD) below it. This combination of the analyser and PSD gives the complete information of the outgoing wave vectors from each detected point on the PSDs. The idea has been first...
Mn2GaC (space group P63/mmc) is a laminated material consisting of Mn2C layers interleaved with Ga layers. The competition between antiferromagnetic and ferromagnetic interactions within the Mn2C planes gives rise to complex magnetic behaviors. It orders magnetically below TN = 507 K and shows another magnetic transition at TC = 220 K. We employed neutron diffraction to study the nature of the...
The family of materials (Mn(Sb,Bi)$_2$Te$_4$)((Sb,Bi)$_2$Te$_3$)$_m$ offer a smörgåsbord of topological electronic states and magnetic phenomena [1-3]. The hexagonal MnSb$_4$Te$_7$ is one such van der Waals material. The unit cell can be described by the $P\bar{3}m1$ space group, where the Sb$_2$Te$_3$ topological layers are sandwiched between magnetic MnSb$_2$Te$_4$ septuple layers....
Small-angle neutron scattering in the comprehensive analysis of particulate systems brings a number of benefits in a deeper understanding of physicochemical processes. The method is capable of providing a detailed structural description at the mesoscale level. Such a description must contain information about polydispersity. There are many approaches to determining the size distribution...
The possibility to measure neutron transmission spectra in each pixel of imaging dataset enables various studies of microstructure within solid materials. Among these studies there is a possibility to map the temperature distribution within materials without direct access to them, e.g. enclosed within other structures. Variation of both Bragg edge wavelength and the width of neutron resonance...
The phonon density of states (PDOS), which plays an important role in the mechanisms that determine the unique physical properties of nanocrystals (NCs), strongly depends on the reduced size of the NC.
While these confinement effects are often invoked to explain surprising results, the direct study of lattice dynamics in NCs is difficult.
Theoretically, it is shown that as the NC size...
By utilizing time-of-flight neutron reflectometry (ToF-NR) under different relative humidities, we demonstrate that grafted polymer brushes constituted by hydrophilic cyclic macromolecules exhibit more compact conformation with lower roughness compared to linear brush analogues, due to the absence of dangling chain ends extending at the interface. [1] In addition, due to increased interchain...
SAPHiR is an instrument-under-construction designed for neutron diffraction and radiography under extreme pressure and temperature conditions at the FRM II neutron source. A multianvil press with six independently controlled rams subjects powder, fluid, and melt samples with volumes of 10–50 mm3 to a current maximum pressure of 15 GPa and temperatures up to ca. 2300 K. An additional...
easyScience[1] is an initiative from the European Spallation Neutron Source (ESS) to unify simulation software across neutron scattering. DON’T PANIC! While this goal seems an unsurmountable challenge, it is achievable as demonstrated by our current releases. The easyScience project has the following aims; Provide a unified method to interact the most popular technique specific simulation...
Incommensurate spiral magnets have raised tremendous interest in recent years, mainly motivated by their wealth of spin structures with potential non-trivial topology, such as skyrmions. A second field of interest is multiferroicity: Helical spin structures are in general ferroelectric, enabling the coupling of the electric and magnetic properties. Both fields present enormous potential for...
The McStas[1] Monte Carlo ray-tracing package is a well known and widely adapted tool for the design and optimisation of neutron instrumentation world wide.
The contribution presents an overview of the project in its current state with highlight on new features in the 3.2 and 2.7.2 releases from the fall of 2022.
Further the contribution demonstrates how to easily port an existing 2.x...
TOFTOF is a direct geometry disc-chopper time-of-flight spectrometer. A cascade of seven fast rotating disc choppers is used to prepare a monochromatic pulsed beam which is focussed onto the sample by a converging super-mirror section. The scattered neutrons are detected by 1000 $_3$He detector tubes with a time resolution up to 50 ns. The detectors are mounted at a distance of 4 m and cover...
Recent developments in event driven camera systems allow the construction of a new type of scintillator-based event mode imaging devices. A neutron imaging device employing this new technology to reach high spatial and temporal resolution is currently under development at the NECTAR instrument at FRMII. The goal is for the detector to have a spatial resolution better than 100 μm and a timing...
The new customized SAXS/WAXS instrument from XENOCS have be installed in the JCNS X-ray laboratory from the end of 2021. As a young member of our small angle scattering instrument by using x ray as beam, the new instrument is equipped with a high flux metal-jet source and a moveable Eiger 2R4M SAXS detector. With additional 4-axis motorized WAXS detector and Bonse-Hart USAXS the scattering...
Polarized neutron diffraction is a powerful tool for studying condensed matter physics and to probe the spin and orbital properties of unpaired electrons. POLI is a polarized neutron single crystal diffractometer built on the hot neutron source at MLZ. Currently three standard setups are implemented on POLI: 1) zero-field spherical neutron polarimetry using CRYOPAD; 2) polarized neutron...
The European Spallation Source (ESS), which is currently under construction in Lund, Sweden, will be the most powerful pulsed neutron source in the world. A design study project named HighNESS is dedicated to develop a second neutron source at ESS that compared to the first source, located above the spallation target and designed for high cold and thermal brightness, provides higher intensity...
SOFIA is the horizontal-type neutron reflectometer at Beamline 16 (BL16) of the Materials and Life Science Experimental Facility (MLF) of the Japan Proton Accelerator Research Complex (J-PARC). Allowing users to keep the sample horizontal while measuring the whole q-range, SOFIA is advantageous for observing liquid-vapor and liquid-liquid free interfaces. Thus, SOFIA is, by and large, utilized...
The advent of high-current accelerator systems launched the development of high-current accelerator-driven neutron sources (HiCANS) utilizing low energy nuclear reactions. This development can counteract the increasing shutdown of existing fission-based neutron sources and a resulting decline in available neutron beam days as well as establishing HiCANS as a next generation national neutron...
Neutron supermirrors are the bedrock of all modern neutron beamlines both polarized and unpolarized. However, while the technology has improved remarkably over the last 20 years there are still areas where significant improvements can be made regarding interface roughness reduction, better polarization and elimination of magnetic stray fields when polarizing the neutrons. Adding 11B4C to Fe/Si...
We present a compact 3He polariser to be used as polarisation analyser for KWS1.The 38 cm long magic box magnetic cavity with angled plates on the entrance side provides a 3He magnetic lifetime of 300 hours with the cell centred in the device, up to 7 cm diameter cell is used and polarization is performed with one laser, a relatively large angular coverage providing up to ±0.07 ̊A−1 at 4.5 ̊A...
We consider a dilute ensemble of randomly-oriented noninteracting spherical nanomagnets and investigate its magnetization structure and ensuing neutron-scattering response by numerically solving the Landau-Lifshitz equation. Taking into account the isotropic exchange interaction, an external magnetic field, a uniaxial magnetic anisotropy for the particle core, and in particular the Neel...
Since water has a high impact on the chemical-physical characteristics of Ionic Liquids (IL), both as a contaminant or as cosolvent, the detailed knowledge of the intermolecular interactions in IL/water solutions is a crucial step for understanding and predicting the range of properties of these non-conventional solvents for applications in many fields including electrochemistry, biochemistry,...
To date, several materials have been proposed as hosts for the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) spatially modulated superconducting state [1], but direct experimental proof has been challenging, with only the organic superconductors providing uncontested evidence for the state [2]. The FFLO state is expected to develop at high fields and low temperatures in materials with strong Pauli...
We have extended our previous investigations on self- and collective dynamics of liquid water [1,2] to the case of tetrahydrofuran (THF). Neutron polarization analysis on a wide-angle time-of-flight spectrometer (PLET @ ISIS) has allowed measuring separately coherent and incoherent dynamic structure factor of deuterated THF with sub-meV resolution in a wide scattering vector (Q) range. The...
ORSO is a group of reflectometry scientists from across the globe that are interested in im-proving neutron and X-ray reflectometry through collaboration. The aims and focus of our working groups are arranged as follows:
• The education and outreach working group aims to develop understanding of reflec-tivity techniques and disseminate information about reflectivity analysis.
• The File...
The development of the Sample Environment Communication Standard and its relase is a huge achievement. Since a standard is only good if it is applied, at SINQ/PSI we are in the process to implement SECoP into the data acquisition process. Together with the Maier-Leibnitz-Zentrum Garching/Germany we developed Frappy.
Frappy is a python framework to implement a device communication and...
Technical University of Munich (TUM) is committed to convert its research neutron source Heinz Maier Leibnitz (FRM II) to a lower enriched fuel. Since 2004, TUM together with its European and International partners develops new high-density fuels and tools for reactor core modelling for the conversion of FRM II. As today, three fuel options are on the way to be qualified for conversion:...
In biological environments, proteins are exposed to polydisperse surrounding. The interaction of this environment is essential for a correct function of the cell and disfunctions may lead to diseases. To understand the diffusive properties of proteins in polydisperse environments, we performed several quasi-elastic neutron scattering (QENS) experiments. Changes in the probed short-time...
Metal organic magnets (MOM) have enormous potential to host a variety of electronic and magnetic phases that originate from a strong interplay between the spin, orbital, and lattice degrees of freedom. Due to the unique possibility of controlling interatomic distances and magnetic exchange pathways by coordination chemistry, a plethora of MOM have been reported. This way, 0D to 3D magnetic...
We have studied room-temperature neutron and X-ray crystal structures of the triosephosphate isomerase Glu97Gln variant in complex with the inhibitor 2-phosphoglycolate (PGA) that mimics a reaction intermediate. The results clearly show that Glu-167 is protonated and hydrogen bonded to the carboxylate group of the inhibitor. The other carboxylate atom of PGA forms a hydrogen bond to Lys-13,...
Proteins are biological macromolecules built from a sequence of amino acids with varying characteristics as hydrophobicity, charge and side-group that determine their biological and physical properties. Unfolded proteins, like intrinsically disordered proteins (IDPs), share similarities with polymers in structure and dynamics. For thermal unfolded Ribonuclease A or the IDP myelin basic protein...
Materials with geometrically frustrated lattice structures are highly interesting as they often exhibit unconventional phases of matter. While most research on frustrated materials has been performed on insulating spin systems, only little work has been done on magnetically frustrated metallic systems. Notably, one of the pressing question in the field is how frustrated interactions can affect...
In the superconductor Niobium the vortex-vortex interaction shows in addition to the purely repulsive also an attractive term. This leads to the formation of the intermediate mixed state (IMS) where flux-free Meissner state domains and vortex clusters coexist. Besides being a prominent example of exotic vortex matter this two-domain structure can also act as a highly tunable model system for...
Metal organic frameworks (MOFs) are crystalline materials that contain metal-ion nodes and organic ligands as linkers to form 1-, 2-, and 3-D structures. Their structural versatility and multifunctional properties have sparked much interest in advanced materials synthesis. Due to their modular nature, many of these materials can be constructed by design. Over the last decade there are several...
Cellular membranes are essential components of cells that compartmentalize cellular events, control communication between compartments and with the exterior, enable the formation of gradients of ions and other solutes, and provide a proper environment for the large percentage of proteins that are membrane bound or associated to it1. The ability to carry out this diverse array of essential...
The High Brilliance Neutron Source (HBS) is expected to be the next-generation neutron facility, which uses low proton energy (70MeV) to achieve high neutron brilliance. As the moderator-reflector unit is correlated to the neutron moderation, reflection, and transportation, designing a suitable moderator-reflector unit is one of the important issues for achieving the “high brilliance” of the...
The Institut Laue-Langevin has been performing experiments at the cutting edge of research for more than 40 years now, in fields as varied as molecular biology, chemistry, fundamental physics, materials science and the environment. The ILL provides the scientific community with 40 high-performance instruments constantly maintained at the highest state of the art.
To exploit the full...
The syntheses of aluminum substituted strontium hexaferrite nanoparticles, SrFe12-xAlxO19 with x=0-3, via three different preparation methods were investigated: hydrothermal autoclave synthesis (AC), a citrate sol-gel synthesis (SG) and a solid-salt-matrix (SSM). Evaluation of macroscopic magnetic properties revealed that for the SG sample...
The standard project management methodologies were developed to serve a world where the business objectives are focused on financial benefit. Such methodologies with emphasis on delivering programmes and projects within the triple constrain need to be strongly adapted to the unique environment of research infrastructures (RIs). Even the definition of project, programme and portfolio needs to...
Two-dimensional van der Waals materials host a diverse landscape of optical, electronic and topologically non-trivial states in the monolayer limit and have therefore fuelled a search for the next candidate materials that may enable novel information technologies. The magnetic features can be controlled by different processes including thickness, doping and other tuning parameters. CrI3...
We present developments towards spin-selective in-situ detection of ultracold neutrons, motivated by the search for a permanent electric dipole moment. Magnetic fields generated by microstructured superconductors will produce a spin-dependent shift of the neutron-optical potential at a reflecting surface layer. Low-field-seeking neutrons then penetrate to an underlying absorber with...
In December 1997 the OSIRIS beamline at the ISIS Facility, UK, recorded its first neutron spectrum. The instrument enjoyed a first stint as a cold neutron diffractometer before the spectroscopic capabilities were fully commissioned. OSIRIS soon became a workhorse QENS spectrometer as well a highly successful cold neutron excitations spectrometer. The status of the instrument is recognized by...
The ILL Deuteration Laboratory is a platform dedicated to isotope labelling of biological molecules. More specifically, the D-Lab team members are experts in the deuteration of biomolecules for neutron applications, such as neutron scattering, protein crystallography, dynamics and reflectometry. The D-Lab is part of the ILL Life Sciences Group within the Partnership for Structural Biology...
The reflected neutron flux from state-of-the-art neutron multilayer mirrors is hampered primarily by insufficient layer definitions. To achieve the ultimate flat and abrupt interfaces (±½ atomic layer), the mirror should be made as a single crystal, artificially layered, heteroepitaxial structure (superlattice, SL). Here we explore CrBx/TiBy (0001)/Al2O3 (0001) SL mirrors, grown by magnetron...
Hybrid aerogels in general are promising scaffolds for bone regeneration owing to the high porosity, nanostructured surface and versatile functionalization of this family of sol-gel materials. Our study focuses on the design, synthesis, in-depth structural characterization and in vitro biological testing of calcium(II)-containing hybrid borosilicate aerogels. Little is known about the behavior...
We present a general classification [1, 2] to answer the question: which groups allow to describe a given magnetic, electric and toroidal polarisation mode? These three classifications are based on magnetic point groups used in two contexts: (i) the magnetic point group of the magnetic crystal class and (ii) the magnetic site symmetry point group of the Wyckoff position of interest. The...
Iron oxide nanoparticles are presently considered as promising objects for various medical applications including targeted drug delivery and magnetic hyperthermia. The nanoparticle solution in water has to posses large enough saturation magnetization to react on external magnetic field. However, there remains several unsolved questions regarding the effect of size onto nanoparticle overall...
Neutron scattering is well-suited to the study of biological membrane lipids and has the potential to contribute unique view into the role membranes play in both health and disease, as well as medical treatments, by employing deuterium labeling. However, modeling the lipid environment in living cells poses a challenge due to their complex and tightly-controlled composition. By extracting and...
T-REX is a bispectral direct geomentry neutron chopper spectrometer, currently being constructed at the ESS. The instrument is a collaboration between Forschungszentrum Jülich and Consiglio Nazionale delle Ricerche (CNR).
T-REX is a very versatile instrument and will mainly focus on probing single crystals in the scientific areas of low dimensional, topological and frustrated materials,...
At the Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) of the Technical University of Munich (TUM) a new source for ultra-cold neutrons (UCN) with a solid deuterium converter is currently under construction. The source is designed to deliver UCN to four different experiments simultaneously, located in the experiment hall and neutron guide hall east of FRM II. This poster shall give an...
We present a concept of a GISANS instrument for the High Brilliance Source (HBS), a High Current Accelerator-based Neutron Source (HiCANS) using a moderate energy proton accelerator which allows very compact moderators and shielding, and flexible pulse repetition rates. The general layout resembles a classical SANS instrument with 10 m collimation and 10 m detector distance. In the beam...
The scattering of light, X-rays, electrons or neutrons by matter is used widespread for structural characterization from atomic to macroscopic length scales. With the advent of high-brilliance beam sources and the development fast, large area pixelated detectors, scattering patterns are now acquired at unprecedented frame rates and frame sizes. The slow analysis of these scattering patterns...
Owing to low density (3.8-4.0 g/cm3), high specific strength and stiffness, excellent creep resistance and good corrosion resistance, the β-solidifying γ-titanium aluminide with properly aligned (α2+γ) lamellar-structure have been considered as excellent candidates for modern turbine blades. Recently, it has been evidenced that when the γ lamellae are oriented to the load direction the...
Diffraction used in conjunction with molecular deuteration provides a model independent means to examine detailed structural and compositional information of model and real biological membranes in the lamellar phase. The technique provides specific information of localization of molecules and smaller units with respect to the unit cell. Deuteration is used to provide specific labelling and...
In 2023, the user program at SINQ, Paul Scherrer Institut (PSI), will again offer two small-angle instruments, the new SANS-LLB and as before SANS-I. SANS-LLB is the adapted and optimised PA20 SANS instrument from the Laboratoire Léon-Brillouin (LLB) that was transferred to PSI after the shutdown of the Orphée reactor in 2019 and will be operated by LLB and PSI. SANS-LLB is a general-purpose...
Bound coherent scattering lengths b(coh) are one of the basic properties of any isotope, and many experimental neutron techniques in condensed matter as well as in nuclear physics rely on these values, determined by many different scientists over decades and collected in various tables. But many of the values listed in these respectable references have large experimental uncertainties,...
CuMnSb is a half Heusler alloy which orders type-II antiferromagnetically and is, thus, unique among the 3d transitional metal heusler alloys. Theoretical calculations suggested that type-II antiferromagmetism is not the energetically favored state and is only stabilized by structural defects. Further, a high quality CuMnSb single crystal exhibits a additional phase transition within the...
KOMPASS is a polarized cold-neutron three axes spectrometer (TAS) currently undergoing its final construction phase at the MLZ in Garching. The instrument is designed to exclusively work with polarized neutrons and optimized for zero-field spherical neutron polarization analysis for measuring all elements of the polarization matrix. In contrast to other TASs, KOMPASS is equipped with a unique...
We present new scattering kernels for two materials of interest as cold and very cold neutron moderators: solid Methane in phases I &II and solid Ethane in phase III, based on simple models that include the main dynamical features of those three systems and the effect of spin correlations.
Inelastic neutron scattering experiments were performed using the TOSCA spectrometer at the ISIS...
Wormlike micelles may serve as a model system for linear polymers and are studied extensively. Micelles, unlike polymers, can break and reform. Their self-assembled structure makes them unique in applications where high shear rates may be encountered, such as drag reduction, and as a templates for materials synthesis. The rheological properties of viscoelastic materials can be described by the...
Proteins are complex molecular systems whose internal dynamics is
characterized by a vast spectrum of time scales, ranging from
sub-picoseconds for vibrations of chemical bonds to seconds and beyond
for large conformational rearrangements. Using a "minimalistic"
multi-time scale model for the relaxation dynamics of
proteins~[1,2], we show here that even small changes due to external...
Products derived from milk or plant based emulsions by gelation like cheese or yoghurt have a large range of structural features from atomic to macroscopic length scales. Scattering techniques with neutrons and x-rays provide an unique view into this fascinating world of interfaces and networks provided by proteins and lipids. Combining these ensemble averaging scattering techniques with a...
We present a new cryomagnet development for ESS, principally for use on the MAGiC instrument, but also suitable for other diffraction instruments in the ESS suite. In order to take advantage of the large detector area and polarised beam, a very large, asymmetric, aperture has been prioritised, with a maximum field of 8 T. The bore size is 50 mm, to allow for ULT inserts and bulky samples such...
High quality gluten-free food alternatives are increasingly sort after as supplements for people requiring diets with low glycaemic indexes. The challenge to produce alternatives with high enough quality to meet consumer demands. Structure at the nanoscale is highly related to the texture, quality, mouthfeel of the final product. Here, we perform for the first time a structural...
A new methodology for the determination of self-diffusivities in solids and the corresponding activation energy of diffusion using in-situ Neutron Reflectometry is presented. In contrast to the classical ex-situ approach based on a sequence of isothermal measurements at different temperatures, the in-situ method allows one to work with a single experiment based on ramping the temperature with...
The three-axis spectrometer IN8 offers to ILL users advanced conditions for studies of thermal excitations in single crystals and liquids. The instrument performance and flexibility are ensured by the use of large double-focusing monochromators and analysers with independently variable and remotely controlled horizontal and vertical focusing (bending) of the crystal reflecting planes providing...
In frustrated magnetic systems, the competition amongst interactions can introduce extremely high degeneracy and prevent the system from readily selecting a unique ground state. In such cases, the magnetic order is often exquisitely sensitive to the balance among the interactions, allowing tuning among novel magnetically ordered phases. We present antlerite, Cu$_3$SO$_4$(OH)$_4$, as a...
Small-angle neutron scattering is a very versatile technique which can be applied in virtually any field of neutron science, be it soft matter, biological or medical sciences, material science, hard matter or magnetic materials. In all those fields, SANS helps investigate structure on the nano-scale from a few nanometers up to several hundred nanometers.
In order to achieve this, SANS has...
Microgels are stimuli responsive polymers with possible applications e.g. for drug delivery. A key feature of them is the sudden shrinkage, induced by temperature or other external parameters, called Volume Phase Transition (VPT). The VPT is intrinsically connected to the water-polymer, or more generally to the solvent-polymer interaction. PNIPAM in ethanol, e.g. remains swollen also at higher...
Neutron scattering allows for quite complicated sample environments with control over the sample conditions, such as controlled temperature, as well as the presence of strong magnetic fields.
The presence of magnets in scattering experiments necessitates a significant amount of materials in the structure. The coils of the magnets, which are not in the direct beam, add more material into the...
Small-angle scattering is an increasingly common method for characterizing particle ensembles in a wide variety of sample types and for diverse areas of application. SASfit has been one of the most comprehensive and flexible curve fitting programs for decades, with many specialized tools for various fields. Here, a selection of enhancements and additions to the SASfit program are presented...
The idea of quantum spin liquid (QSL) on the triangular lattice was proposed by P. Anderson in 1973. Since his work, a lot of theoretical and experimental efforts have been made to explore deeper this state. Here we present the results for the combined study of structural and dynamic properties in application to the polycrystalline CuSb$_2$O$_6$ sample. The diffraction experiments using both...
Neutron reflectometry is used by a wide community of scientific groups addressing questions in many different fields, including materials science, magnetism, polymer physics and biophysics. The analysis of reflectivity data from instruments around the world is traditionally performed either with computer programs that use a graphical user interface for building simple slab models of the...
The HBS is a high brilliance accelerator driven neutron source currently in the design process. It provides different target stations that follow the same duty cycle but offer different frequencies and pulse length. Cold and thermal moderators are used to adjust the neutron spectrum. The target stations with its moderators thus allow choosing the parameters best fitting to an instrument or...
The sol-gel auto-combustion method and the sonochemical co-precipitation method were used to prepare Ba0.5Sr1.5Zn2Fe12O22 (S1) and partially Al substituted Ba0.5Sr1.5Zn2Al0.08Fe11.92O22 (S2) powders. The XRD analyses show that the samples are single-phase Y-type hexaferrite. SEM images of the S1 sample obtained by auto-combustion revealed particles of a very non-uniform shape and...
H2V3O8 (HVO) is a promising high-capacity cathode material for lithium-ion batteries (LIB). It allows reversible two-electron transfer during electrochemical lithium cycling processes, yielding a very attractive theoretical capacity of 378 mAh g–1. Aimed at providing insights into the lithium storage behavior of HVO, we employed a combination of high-resolution synchrotron X-ray and neutron...
In the evaluation of capability gaps in the initial instrument suite, the European Spallation Source (ESS) has identified a dedicated surface scattering beamline as a high priority for the next phase of instruments. Therefore, a wide consortium, building on the strength in surface and interface science in Sweden, has formed to push for a project to design and construct such an instrument at...
Single chain nanoparticles (SCNPs) are unimolecular polymer chains folded or collapsed via intra-molecular cross-linking under high dilution, leading to sparse conformations and a topological polydispersity similar to that of intrinsically disordered proteins (IDPs). Currently, there is great interest in expanding this technology to biodegradable and biocompatible polymers, including proteins....
ISIS Neutron and Muon Source is now seeking its next phase of new instruments and significant upgrades to existing instruments: a portfolio of projects that has been called the Endeavour Programme. Endeavour will increase both capacity and capability of the facility to address 21st century challenges and enable research in areas such as advanced materials and manufacturing, clean energy...
The octahedrally and tetrahedrally coordinated Fe3+ (S=5/2) ions in Bi2Fe4O9 form a quasi two-dimensional Cairo pentagonal lattice (Pbam). Combined with predominantly antiferromagnetic interactions, this leads to a strong frustration with Tn=245 K while θCW=1670 K in a fairly unexplored geometry. The magnetic structure for T < Tn can be indexed with k=(½, ½, ½) with a noncollinear magnetic...
Apart from fission and spallation, neutrons can also be generated by nuclear reactions induced by protons in the MeV range. This is now applied in High-Current Accelerator-driven Neutron Sources (HiCANS), which are able to reach performances like medium sized reactor or spallation sources. One of these projects is the High Brilliance neutron Source (HBS) at Forschungszentrum Jülich, which is...
With the transformative development of event-based detectors, new perspectives for detection systems for various types of radiation were opened up. A recently developed event-driven imaging system based on Timepix3 sensor technology is capable of observing and time-stamping the optical signal induced by particle interactions in scintillator materials with nanosecond temporal and micrometer...
Spin and charge stripe correlations and their dynamics have been well explored in the ordered state of La-based 214-nickelates for last 3 decades. Recently, we have also explored magnetic excitations in the ordered spin-stipes phases of hole-doped Pr-based nickelates Pr$_{2-x}$NiSrO$_{4+\delta}$ [1-3]. In this regards, what remains less explored is the fluctuating state of the spin stripes...
Neutron and X-ray scattering are well-established techniques to understand the material structure and different phenomena within the systems. However, the structure can not be uniquely determined from the scattering experiments due to the phase problem, i.e. two different structures can yield the same scattering curve. Also, it is important to explain the reasons behind the phenomena observed...
Spin caloritronic materials are currently in the spotlight due to their potential exploitation in the next generation of spintronics applications. Composite systems, consisting of magnetic-insulator (MI) and heavy-metal (HM) bilayers, combine both spintronic and thermoelectric functionalities by interconversion of charge-, spin-, and heat-currents. A prominent example are devices exploiting...
The use of polarized neutrons is very important to cover new science cases and polarized neutrons. Polarized neutrons will be made available on many European Spallation Source (ESS) instruments. There are a number of technologies available for polarizers and polarization analyzers, among them polarizing supermirror and polarized 3He, which will both be used at the ESS. The selection of the...
We report on the results of powder neutron diffraction of Ni$_2$V$_2$O$_7$. Two crystallographic Ni$^{2+}$-ion sites carrying spin-1 exist. Magnetic phase transitions occur at $T_{\rm N1} = 6.7$ and $T_{\rm N2} = 5.7$ K. A 1/2 quantum magnetization plateau appears between 8 and 30 T at 2 K.
We carried out neutron diffraction experiments at 0 T using the HRPT diffractometer at PSI. The...
The MIEZE (Modulated IntEnsity with Zero Effort) resonant spin-echo technique at the RESEDA instrument at FRM II has its optimum resolution at small scattering angles, i.e. SANS type geometries. Recent upgrades (MIASANS) have further increased the resolution in the small angle regime. Going forward, there is the possibility [1] to extend the optimum MIEZE resolution to wide angles by...
Neutron Spin Echo (NSE) spectroscopy uses polarized neutrons; however, it was never used for performing polarization analysis at the same time, which can offer a very promising extension. In NSE experiments one requires a polarizer for preparing the precessing polarization of the incoming neutron beam and a polarization analyzer for observing the precessing polarization of the scattered beam. ...
Complementary use of scattering methods and molecular dynamics (MD) makes it possible to elucidate structural details of complex molecular systems such as biological or electrochemical interfaces.
Although several softwares aiming at some of the tasks involved in the process have been described in the past, an easy to use, well documented and tested, fully FOSS, solution was lacking.
In this...
Co-assembly of oppositely charged polyelectrolytes with proteins is a well-studied approach for designing stimuli-responsive nanocarriers for targeted drug delivery. [1,2] However, the complexity of protein structure limits the ability to predict and tune properties of the formed nanoparticles. The ultimate goal of our research is to reveal the main triggers for the morphological transition of...
Superalloys are key materials of our modern society. They are not only used in harsh environments of power plants for energy conversion but also in aerospace or marine applications, as they combine excellent mechanical properties at high homologous temperatures with very good oxidation and corrosion resistance. To further improve the efficiency of engines, advanced superalloys with improved...