Microscopic mechanism of low thermal conductivity in lead-telluride

Autor: Shiga, Takuma, Shiomi, Junichiro, Ma, Jie, Delaire, Olivier, Radzynski, Tomasz, Lusakowski, Andrzej, Esfarjani, Keivan, Chen, Gang
Rok vydání: 2012
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevB.85.155203
Popis: The microscopic physics behind low lattice thermal conductivity of single crystal rocksalt lead telluride (PbTe) is investigated. Mode-dependent phonon (normal and umklapp) scattering rates and their impact on thermal conductivity were quantified by the first-principles-based anharmonic lattice dynamics calculations that accurately reproduce thermal conductivity in a wide temperature range. The low thermal conductivity of PbTe is attributed to the scattering of longitudinal acoustic phonons by transverse optical phonons with large anharmonicity, and small group velocity of the soft transverse acoustic phonons. This results in enhancing the relative contribution of optical phonons, which are usually minor heat carrier in bulk materials.
Comment: 18 pages, 4 figures, accepted for publication in Phys. Rev. B
Databáze: arXiv