Prof.
Jörg Neugebauer
(Max-Planck-Institut für Eisenforschung GmbH)
15/09/2015, 13:30
DyProSo2015 Main track
Invited Talk
A key requirement in developing systematic approaches to explore and predict properties of materials not yet synthesized is the availability of accurate computational tools determining energies not only at T = 0 K but also under realistic finite temperature conditions. A critical step towards this goal is the ability to accurately describe all relevant excitation mechanisms such as phonons,...
Prof.
Brent Fultz
(California Institute of Technology)
15/09/2015, 10:55
DyProSo2015 Main track
Invited Talk
J.W. Gibbs founded the field of materials science, basing it on the concept of free energy, G = E - TS + PV. For the past century, free energies of materials have been tabulated from measurements of heat capacities, which do not identify the physical sources of enthalpy and entropy. For the past 30 years, it has often been possible to calculate E and PV, but the entropy S has remained more...
Dr
Françoise Damay
(LLB, France)
16/09/2015, 13:30
DyProSo2015 Main track
Talk
Layered triangular antiferromagnet selenide AgCrSe2 (SG : R3m) has been investigated by means of elastic and inelastic neutron scattering, combined with electrical transport, Seebeck coefficient, magnetisation and heat conductivity (kappa) measurements, in the range 5 to 300 K. Below TN = 55 K [1], long-range magnetic ordering is identified, characterized by long-wavelength incommensurate...
Mr
Frank Weber
(Karlsruhe Institute of Technology)
15/09/2015, 11:35
DyProSo2015 Main track
Talk
The interactions of spin, lattice and electronic degrees of freedom in materials are at the origin of complex phase diagrams resulting in new emergent phenomena and technical applications. The coupling between lattice and electronic degrees of freedom is well understood, and the interaction between spin and electronic excitations has been investigated intensely, e.g., in the research on...
Dr
Marek Pasciak
(Institute of Physics of the Czech Academy of Sciences)
15/09/2015, 14:10
DyProSo2015 Main track
Talk
Lead zirconate (PZO) has been recently a subject of intensive studies with its antiferroelectric (AFE) phase transition (PT) being in a spotlight. Since there is no direct link between the paraelectric cubic phase and the low temperature orthorhombic one, the process leading to the emergence of AFE order is not obvious. Results of X-ray inelastic as well as Brillouin scattering experiments has...
Mr
Pascal Neibecker
(Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, Lichtenbergstr. 1, 85748 Garching, Germany)
16/09/2015, 13:55
DyProSo2015 Main track
Talk
The availability of accurate phonon dispersions for all temperatures up to the melting point is essential for the prediction of thermodynamic stabilities of crystal structures. Standard ab initio approaches are based on a quasiharmonic (QH) approximation of the interaction potential, where temperature dependencies enter only via the volume expansion. We have recently developed an extension of...
Dr
SYLVAIN PETIT
(CEA)
16/09/2015, 14:20
DyProSo2015 Main track
Talk
Geometrical magnetic frustration is a central concept in condensed matter physics. In this field, rare earth pyrochlore magnets R2Ti2O7 (R is a rare earth) play a prominent role, as they form model systems showing a rich variety of ground states, depending on the balance between dipolar, exchange interactions and crystal field [1]. The Terbium compound Tb2Ti2O7 remains a cooperative...
