Large Nernst effect and possible temperature-induced Lifshitz transition in topological semimetal YbMnSb 2

作者：Sheng Xu, Chenxi Jiang, Shuxiang Li, Junjian Mi, Zheng Li, Tian‐Long Xia, Tao Qian, Zhu‐An Xu · 发表于：Physical review. B./Physical review. B · 年份：2023 · DOI：10.1103/physrevb.107.245138 · 被引用次数：7 · 研究领域：Topological Materials and Phenomena、Advanced Thermoelectric Materials and Devices、Quantum and electron transport phenomena

Topological materials provide an interesting platform in the study of thermoelectric effect due to their novel electronic properties. Here we report the magneto-Seebeck (MS) effect, large Nernst effect, and a possible temperature-induced Lifshitz transition in topological semimetal ${\mathrm{YbMnSb}}_{2}$. It exhibits evident quantum oscillations in the MS effect from which six frequencies are extracted and a light effective mass of ${F}_{4}$ is obtained. The large Nernst effect with the Nernst thermopower of about 40 $\textmu{}{\mathrm{VK}}^{\ensuremath{-}1}$ is discovered around 120 K and 14 T. Combining the analysis of the first-principles calculations and the Hall effect, we suggest that the large Nernst signal could mainly stem from the Dirac bands-induced high mobility and small Fermi energy (${\ensuremath{\varepsilon}}_{F}$). Besides, it could be further enhanced by the modified carrier properties resulting from the temperature-induced Lifshitz transition through the so-called ambipolar effect.