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arXiv · 2207.11480

Topological quantum transition driven by charge-phonon coupling in higher-order topological insulators

Congwei Lu·Mei Zhang·Haibo Wang·Qing Ai·Tao Liu
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Abstract

We investigate a second-order topological quantum transition of a modified Kane-Mele model driven by electron-phonon interaction. The results show that the system parameters of the bare modified Kane-Mele model are renormalized by the electron-phonon interaction. Starting from the second-order topological phase for the bare model, the increasing electron-phonon coupling strength can drive the second-order topological insulator into a semimetal phase. Such a secondorder topological phase transition is characterized by the band-gap closing, discontinuity of averaged ferminoic number and topological invariant.

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Congwei Lu, Mei Zhang, Haibo Wang, Qing Ai, Tao Liu. 2022-07-23. Topological quantum transition driven by charge-phonon coupling in higher-order topological insulators. https://doi.org/10.1103/physrevb.107.125118

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