- By:
- Sergueev, I.; Glazyrin, Konstantin; Kantor, Innokenty; McGuire, Michael A; Chumakov, A.; Klobes, B.; Sales, Brian C; Hermann, Raphael P
- Journal Name:
- Physical Review B
- Page Number:
- 224304
- Volume:
- 91
- Issue Number:
- 22
- Publication Date:
- June 15, 2015
- View DOI Listing:
- https://doi.org/10.1103/PhysRevB.91.224304
Abstract
A high-pressure study of the lattice dynamics in the filled skutterudite Eu0.84Fe4Sb12 was carried out by means of x-ray powder diffraction and nuclear inelastic scattering. The anharmonicity of particular phonon modes was characterized by mode and element specific Gr¨uneisen parameters. The large anharmonicity of the rattling optical mode that is hybridized with the acoustical phonons at ambient pressure is reduced at high pressure as the phonon modes decouple. This result suggests that anharmonic coupling between acoustic and optical phonon modes plays a central role in the reduced thermal conductivity.
