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arXiv · 2011.07548

Topological $s$-wave superconductors driven by electron correlation

Huai-Shuang Zhu·Zhidan Li·Qiang Han·Z. D. Wang
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Abstract

It is interesting to ask whether electron interaction can turn a topologically trivial superconductor into a nontrivial one without the presence of spin-obital coupling. In this paper we solve a correlated $s$-wave superconducting model exactly. The variation of the fermion number parity of the superconducting ground state as a function of the electron interaction is calculated and the topological phase diagram is obtained. Topological $s$-wave superconducting states are revealed in the doped Mott insulators, which is further confirmed by the numerical investigation of the topological boundary zero mode.

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Huai-Shuang Zhu, Zhidan Li, Qiang Han, Z. D. Wang. 2020-11-15. Topological $s$-wave superconductors driven by electron correlation. https://doi.org/10.1103/physrevb.103.024514

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