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.
@article{arxiv.2011.07548,
title = {Topological $s$-wave superconductors driven by electron correlation},
author = {Huai-Shuang Zhu and Zhidan Li and Qiang Han and Z. D. Wang},
journal= {arXiv preprint arXiv:2011.07548},
year = {2021}
}