Toriyama Michael Y, Snyder G Jeffrey
Northwestern University, Evanston, IL 60208, USA.
Innovation (Camb). 2025 Jan 22;6(3):100782. doi: 10.1016/j.xinn.2024.100782. eCollection 2025 Mar 3.
Thermoelectric properties of topological insulators have traditionally been examined in the context of their metallic surface states. However, recent studies have begun to unveil intriguing thermoelectric effects emerging from the bulk electronic states of topological insulators, which have largely been overlooked in the past. Charge transport phenomena through the bulk are especially important under typical operating conditions of thermoelectric devices, necessitating a comprehensive review of both surface and bulk transport in topological insulators. Here, we review thermoelectric properties that are uniquely observed in topological insulators, placing special emphasis on unconventional phenomena emerging from bulk states. We demonstrate that unusual thermoelectric effects arising from bulk states, such as band inversion-driven warping, can be discerned in experiments through a simple analysis of the weighted mobility. We believe that there is still plenty to uncover within the bulk of topological insulators, yet our current understanding can already inspire new strategies for designing and discovering new materials for next-generation thermoelectrics.
传统上，拓扑绝缘体的热电性质是在其金属表面态的背景下进行研究的。然而，最近的研究开始揭示出拓扑绝缘体体电子态中出现的有趣热电效应，而这些效应在过去很大程度上被忽视了。在热电装置的典型工作条件下，通过体的电荷传输现象尤为重要，因此有必要对拓扑绝缘体中的表面和体传输进行全面综述。在此，我们回顾了拓扑绝缘体中独特观察到的热电性质，特别强调了体态中出现的非常规现象。我们证明，通过对加权迁移率的简单分析，在实验中可以辨别出由体态引起的异常热电效应，如能带反转驱动的翘曲。我们相信，在拓扑绝缘体的体相中仍有许多有待发现的东西，但我们目前的理解已经可以为设计和发现下一代热电新材料提供新的策略。
