APL Materials (Apr 2020)
Topological thermoelectrics
Abstract
Since the first-generation three-dimensional topological insulators were discovered in classic thermoelectric systems, the exploration of novel topological materials for advanced thermoelectric energy conversion has attracted increasing attention. The rapid developments in the field of topological materials, from topological (crystalline) insulators, Dirac/Weyl semimetals, to magnetic Weyl semimetals, have offered a variety of exotic electronic structures, for example, topological surface states, linear Dirac/Weyl bands, and large Berry curvature. These topological electronic structures provide a fertile ground to advance different kinds of thermoelectric energy conversion based on the Seebeck effect, magneto-Seebeck effect, Nernst effect, and anomalous Nernst effect. In this Perspective, we present a vision for the development of different topological materials for various thermoelectric energy conversion applications based on their specific topological electronic structures. Recent theoretical calculations and experimental works have been summarized to demonstrate practical routes for this new field. Further outlook on scientific and technological challenges and opportunities with regard to topological thermoelectrics are offered.