Temperature-dependent phonon spectra of magnetic random solid solutions

Temperature-dependent phonon spectra of magnetic random solid solutions

Ikeda, Yuji (Kyoto University; Max-Planck-Institut für Eisenforschung)
Körmann, F.H.W. (TU Delft (OLD) MSE-7; Max-Planck-Institut für Eisenforschung)
Dutta, Biswanath (Max-Planck-Institut für Eisenforschung)
Carreras, Abel (Kyoto University)
Seko, Atsuto (Kyoto University; National Institute for Materials Science; Japan Science and Technology Agency)
Neugebauer, Jörg (Max-Planck-Institut für Eisenforschung)
Tanaka, Isao (Kyoto University; National Institute for Materials Science)

2018

A first-principles-based computational tool for simulating phonons of magnetic random solid solutions including thermal magnetic fluctuations is developed. The method takes fluctuations of force constants due to magnetic excitations as well as due to chemical disorder into account. The developed approach correctly predicts the experimentally observed unusual phonon hardening of a transverse acoustic mode in Fe-Pd an Fe-Pt Invar alloys with increasing temperature. This peculiar behavior, which cannot be explained within a conventional harmonic picture, turns out to be a consequence of thermal magnetic fluctuations. The proposed methodology can be straightforwardly applied to a wide range of materials to reveal new insights into physical behaviors and to design materials through computation, which were not accessible so far.

Computational methods
Magnetic properties and materials
Mechanical properties

http://resolver.tudelft.nl/uuid:80a31b9a-3d11-4f2c-a4cc-f0c2e757e8b8

https://doi.org/10.1038/s41524-018-0063-1

2057-3960

npj Computational Materials, 4 (1)

Institutional Repository

journal article

© 2018 Yuji Ikeda, F.H.W. Körmann, Biswanath Dutta, Abel Carreras, Atsuto Seko, Jörg Neugebauer, Isao Tanaka