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...
The instrument PERC is currently under construction at the FRM II. It aims to measure the beta spectrum of neutron decay more precisely than its predecessors PERKEO II and PERKEO III, enabling the determination of several correlation coefficients in neutron beta decay with an improved precision by one order of magnitude. Of particular interest is the so-called beta asymmetry parameter A which...
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...
Although surfactants have been widely used in skin care and other related applications, our knowledge about how surfactants interact with stratum corneum (SC) lipids remains limited. Our group has systematically studied how surfactants interact with a lipid SC model by neutron diffraction and molecular dynamics (MD) simulations, focusing on examining the impact of surfactant molecular...
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...
The stratum corneum (SC) is a thin layer of anucleated cells in a lipid matrix and forms the outermost layer of skin, often depicted with a brick-and-mortar structure.[1] Understanding the molecular basis of the barrier properties of skin has important implications for diseased states such as atopic dermatitis and for topical application of therapeutics. The self-assembly of the intercellular...
The fluid lamellar phase of lipid bilayers is associated with the normal function of the plasma membrane. The extension of the range of the fluid phase can support an increase of the operational range of environmental conditions for the normal physiological functioning of the membrane. A range of enzymes may be utilized to provide to the lipid bilayer with a means of adapting to changes in...
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...
Liquid-liquid phase separation (LLPS) of intrinsically disordered proteins has attracted a wide attention in the biological and biophysical community, and it is considered as a ‘hot’ topic. We investigated the kinetics of the LLPS of the myelin basic protein (MBP) over several orders of magnitude in time.
MBP is essential for the integrity of myelin sheaths ensuring flawless neuronal signal...
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....
The substrates of enzymes are often insoluble in water. Protein molecules, however, are usually hydrophilic. Nature overcomes this problem by compartmentalization of the cytoplasm and by generating huge interfaces between polar and apolar regions inside the different relevant organelles. For biotechnological applications an approach mimicking this compartment formation has already been...
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...
The replacement of combustion engines with battery-powered electric drivetrains is one of many essential steps to reduce greenhouse gas emissions on the way to a green future, leading to an increasing demand on Li-ion batteries with higher capacities and energy\power densities. Thus, different kinds of mixed lithium transition metal oxide cathode materials have been developed, like high nickel...
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...
One of the major obstacles in acquiring data and developing new techniques for macromolecular studies, is the production of high purity, well behaved, samples. The primary mission of the Biomolecular Labeling Laboratory (BL2) is to provide users the environment, equipment, and expertise necessary to produce stable isotope labeled biomolecular samples to be used for structural and biophysical...
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...
Last decade saw an introduction of low-dimensional neutron moderators, made up of almost pure para-hydrogen. Thanks to the large difference between scattering cross-sections for thermal and cold neutrons, such moderators shaped as tubes or disks can provide a significant brilliance gain over traditional voluminous cold sources. Studies at ESS [1] showed potential gains of 2-3 times in useful...
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...
Electrical steel sheets comprising the magnetic core of electrical machines suffer from energy losses during reversal of magnetization depending on the mobility of the magnetic domains, which is influenced by the treatment of the electrical steel sheet during. Residual stress induced during the manufacturing process (e.g. by blanking the sheets) causes a degradation of domain mobility due to...
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...
Metal alloys, such as LiAl, are gaining more interest as anode materials for lithium ion batteries because they exhibit a high theoretical capacity while being inexpensive. Aluminium has an almost three times higher specific capacity with 993 mAh/g in relation to the commonly used graphite anode. [1] During Lithiation, aluminium begins to form a solid solution with lithium, the so called...
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...
Lithium-ion batteries (LIBs) play an important role in our daily life with a variety of important applicants. To this day, significant resources have been dedicated to the development of high-performance LIBs, particularly the research necessary to identify the optimum electrolyte materials to solve the safety issue. Up to this point polymer electrolytes are widely investigated for their...
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...
Wear causes a loss of 2% to 7% of the gross national product in industrialized countries [1]. Therefore, developing wear-resistant coatings and optimizing their manufacturing processes are essential. A novel metal matrix composite (MMC) coating has been developed via laser melting injection (LMI) technique over the last few years, which consists of a bronze matrix and tungsten fused carbides....
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...
