|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Alloys and Compounds for Thermoelectric and Solar Cell Applications IX
||The Doping Effects on the Thermal Conductivity of GeTe
||Jie Ma, Jiong Yang, Yangzhong Pei, Siqi Lin
|On-Site Speaker (Planned)
GeTe is a thermoelectric material with the superior electronic performance and low thermal conductivity. The high electronic performance arises from the multiple valence bands and highly degenerated band at high symmetric points of Brillouin zone, while the origin of the low thermal conductivity has so far been elusive. As the other IV-monotellurides, PbTe and SnTe, a strong anharmonic coupling between the ferroelectric transverse optic mode and the longitudinal acoustic mode is believed to be existed in GeTe, which plays a central role in explaining the low thermal conductivity. Therefore, the signal of the acoustic-optical phonon coupling in GeTe should be strong around the ferroelectric transition temperature, around 700K, and is the indicator of low thermal conductivity. We conducted inelastic neutron scattering experiments with Ge0.9Bi0.1Te and GeTe0.9Sb0.1, to have a sight of the lattice dynamic of GeTe for further analysis of thermal conductivity.