Fundamental bound on topological gap

Yugo Onishi; Liang Fu

doi:10.1103/physrevx.14.011052

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arXiv · 2306.00078

Fundamental bound on topological gap

Yugo Onishi·Liang Fu

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Abstract

We provide a universal tight bound on the energy gap of topological insulators by exploring relationships between topology, quantum geometry, and optical absorption. Applications of our theory to infrared absorption near topological band inversion, magnetic circular dichorism in Chern insulators, and topological gap in moir\'e materials are demonstrated.

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Yugo Onishi, Liang Fu. 2023-05-31. Fundamental bound on topological gap. https://doi.org/10.1103/physrevx.14.011052

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