Electric and thermal transport properties of topological insulator candidate LiMgBi* *Project supported by the National Key Research and Development Program of China (Grant No. 2016YFA0300604), the National Natural Science Foundation of China (Grant No. 11874417), and the Strategic Priority Research Program (B) of Chinese Academy of Sciences (Grant No. XDB33010100).

Abstract

We report the transport properties of a topological insulator candidate, LiMgBi. The electric resistivity of the title compound exhibits a metal-to-semiconductor-like transition at around 160 K and tends to saturation below 50 K. At low temperatures, the magnetoresistance is up to ∼260 % at 9 T and a clear weak antilocalization effect is observed in the low magnetic-field region. The Hall measurement reveals that LiMgBi is a multiband system, where hole-type carriers (n h ∼ 1018 cm−3) play a major role in the transport process. Remarkably, LiMgBi possess a large Seebeck coefficient ∼440 μV/K) and a moderate thermal conductivity at room temperature, which indicate that LiMgBi is a promising candidate in thermoelectric applications.