Dr
Alexandre IVANOV
(Institut Laue-Langevin, Grenoble)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
We report the new data on the molecular dynamics of water confined in the “channels” of the crystal structure of chrysotile asbestos obtained by neutron spectroscopy. The neutron scattering measurements have been carried out on the time-of-flight spectrometer Sequoia at SNS (Oak Ridge, USA). The energy range up to 600 meV was covered with the instrument conditions selected to emphasize...
Mrs
Dominika Kuźma
(The H. Niewodniczański Institute of Nuclear Physics Polish Academy of Sciences)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
Surfaces and interfaces are waveguides for some kinds of waves. The Stoneley wave occurs on the interface of perfectly bonded isotropic elastic materials [1]. The kind of waves are of importance e.g in geoscience [2] and in the design of delay lines in acoustical waveguides [3]. Whereas the surface Rayleigh wave exists on all free surfaces of elastic media, the range of existence of the...
Dr
Pawel T. Jochym
(Dept. of Computational Material Science, Institute of Nuclear Physics PAN, Cracow, Poland)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
The classical theory of lattice dynamics deals with harmonic crystals. While this theory is very effective with describing large number of physical phenomena connected with lattice vibrations, it leaves out an important aspect of the lattice dynamics: anharmonic effects. Without this component many important physical phenomena cannot be properly described: thermal expansion, phase transitions,...
Dr
Martin Kempa
(Institute of Physics ASCR, Prague)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
Piezoelectric crystals of the Pb(Fe1/2Nb1/2)1-xTixO3 (PFN-xPT) system have drawn much interest in recent years, due to relatively high Curie temperatures and potential multiferroic properties. By substitution of Fe3+/Nb5+ by Ti4+, the magnetic properties are suppressed: the Néel temperature TN decreases rapidly with the Ti content and the Curie temperature TC increases almost linearly....
Mr
Mantas Simenas
(Faculty of Physics, Vilnius University, Sauletekio av. 9, Vilnius, Lithuania LT-10222)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
Recently, a new type of porous materials called coordination polymers or metal-organic frameworks (MOFs) emerged and attracted attention of the scientific community. These crystalline compounds are unique due to the highly porous structures which can be utilized for gas adsorption related applications. Some of MOF materials contain paramagnetic transition-metal ions, resulting in peculiar...
Dr
Vytautas Samulionis
(Vilnius University)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
Composites are considered to be any multiphase materials that show a combination of properties of their components. PZT, CoFe2O4 and BaTiO3 are one of ingredients that can improve the dielectric properties and the ultrasonic properties of polymer based composites. In this work we report on both the dielectric and the ultrasonic properties of the conventional polymer polyvinylidene fluoride /...
Mr
Vilmos Kocsis
(Department of Physics,Budapest University of Technology and Economics)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
Multiferroics allow the magnetic control of electric polarization and the electric control of magnetization via the static magnetoelectric effect (ME). Dynamic or optical ME effects gained high interest because they give rise to unidirectional transmission - as recently observed in low-temperature multiferroics. This phenomenon allows the development of optical diodes, which transmit...
P.J. Graham
(School of Physics, University of New South Wales, Australia)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
Multiferroic materials demonstrate desirable attributes for next-generation multifunctional devices as they exhibit coexisting ferroelectric and magnetic orders. In type-II multiferroics, coupling exists that allows ferroelectricity to be manipulated via magnetic order and vice versa, offering potential in high-density information storage and sensor applications. Despite extensive...
Dr
Jan Petzelt
(Institute of Physics AS CR, Na Slovance 2, 182 21 Prague 8, Czech Republic)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
Recently, we have studied dielectric spectroscopy of variously conducting polyaniline (PANI) pellets in a very broad frequency (10ˇ−2–10ˇ13 Hz) and temperature (10–300 K) range [1]. The DC conductivity varied between ≈10 S/cm for the emeraldine salt and ≈10ˇ–12 S/cm for the deprotonated emeraldine, the PANI base. Mechanism of the conduction consists of polaron transfer along the PANI chains...
Mr
Fabian Ziegler
(Georg-August-Universität Göttingen), Prof.
Götz Eckold
(Georg-August-Universität Göttingen), Dr
Holger Gibhardt
(Georg-August-Universität Göttingen), Dr
Oleg Sobolev
(Georg-August-Universität Göttingen)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
Mullite-type Bi2Mn4O10 [1] is an example for a multiferroic compound with a Néel temperature of 39 K, although its crystal structure [2] is not typical for allowing ferroelectricity. The dipoles of the constituent Mn4+O6 (along c-axis, bond valence sum BVS = 3.90(2) v.u.) and Mn3+O5 (along b-axis, BVS = 3.04(2) v.u.) polyhedra are oriented in different directions [3]. Both its nuclear and...
David Szaller
(Budapest University of Technology and Economics)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
In physical systems simultaneously breaking time-reversal and spatial inversion symmetries the strength of absorption for two counter-propagating light beams can be different irrespective of the polarization state of light [1], which phenomenon is termed as non-reciprocal directional dichroism. Until recent experiments on multiferroic materials [2, 3] this effect was generally found to be...
Mrs
Magdalena Wąsik
(Institute of Technology, Pedagogical University of Cracow, 30-084 Cracow, Podchorazych 2)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
A new family of 2D-like nano-sized binary and ternary transition metal carbides (known also as MXenes) has received significant scientific interest due to their intriguing functionalities and technological applications. Physical and chemical properties of these material can be triggered by terminating their surfaces by various adatoms or molecules. This contribution presents first-principle...
Tobias Weber
14/09/2015, 19:00
DyProSo2015 Main track
Poster
We present measurements of the magnetic field-dependency of the helimagnetic band structure in MnSi. For low fields the helimagnons were previously discovered and mapped out by Janoschek et al. (Phys. Rev. B, 81(21), 214436, 2010) and Kugler et al. (arXiv:1502.06977, 2015), respectively. The high-field ferromagnetic dispersion, on the other hand, has been well known since the 1970s when it was...
Dr
Iñigo Etxebarria
(Fisika Aplikatua II Saila. University of the Basque Country)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
The Aurivillius compound SrBi2Nb2O9 (SBN) has commonly been considered as a potential candidate for nonvolatile memories, and as a consequence, it has been thoroughly investigated both experimentally [1-3] and computationally [4,5]. The phase diagram of SBN is governed by three relevant distortions, and it has been shown that the trilinear coupling among them stabilizes the ferroelectric...
Dr
SYLVAIN PETIT
(CEA)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
Examples of materials where an ``order by quantum disorder" mechanism is at play to select a particular ground state are scarce [1,2]. It has been recently proposed that the anti-ferromagnetic pyrochlore Er2Ti2O7 reveals a most convincing case of this mechanism [3,4,5]. Observation of a spin gap at zone centers was interpreted as a definitive proof of this physics [6]. We argue, however, that...
Mr
Paweł Sobieszczyk
(Institute of Nuclear Physics PAN)
14/09/2015, 19:00
DyProSo2015 Main track
Poster
When encountering a mismatch of characteristic impedance a bulk acoustic wave transforms into up to three reflected and refracted waves of different polarizations. The effect is known as mode conversion [1]. The lack of the specularly reflected wave is called total mode conversion because then all the outgoing waves propagate at speeds different than that of the incident one. Conversely, if...
