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DOE OSTI · 1767736

Two-dimensional topological materials discovery by symmetry-indicator method

Abstract

Two-dimensional (2D) topological materials (TMs) have attracted tremendous attention due to the promise of revolutionary devices with nondissipative electric or spin currents. Unfortunately, the scarcity of 2D TMs holds back the experimental realization of such devices. In this work, based on our recently developed, highly efficient TM discovery algorithm using symmetry indicators, we explore the possible 2D TMs in all nonmagnetic compounds in four recently proposed materials databases for possible 2D materials. We identify hundreds of 2D TM candidates, including 205 topological (crystalline) insulators and 299 topological semimetals. In particular, we highlight MoS, with a mirror Chern number of –4, as a possible experimental platform for studying the interaction-induced modification to the topological classification of materials. Here, our results winnow out the topologically interesting 2D materials from these databases and provide a TM gene pool for further experimental studies.

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BibTeXRIS

Wang, Di, Tang, Feng, Ji, Jialin, Zhang, Wenqing, Vishwanath, Ashvin, Po, Hoi Chun, Wan, Xiangang. 2019-11-07. Two-dimensional topological materials discovery by symmetry-indicator method. https://doi.org/10.1103/physrevb.100.195108

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36 MATERIALS SCIENCE↗