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arXiv · 2212.13013

Intrinsically Interacting Higher-Order Topological Superconductors

Hao-Ran Zhang·Jian-Hao Zhang·Zheng-Cheng Gu·Rui-Xing Zhang·Shuo Yang
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Abstract

We propose a minimal interacting lattice model for two-dimensional class-$D$ higher-order topological superconductors with no free-fermion counterpart. A Lieb-Schultz-Mattis-type constraint is proposed and applied to guide our lattice model construction. Our model exhibits a trivial product ground state in the weakly interacting regime, whereas, increasing electron interactions provoke a novel topological quantum phase transition to a $D_4$-symmetric higher-order topological superconducting state. The symmetry-protected Majorana corner modes are numerically confirmed with the matrix-product-state technique. Our theory paves the way for studying interacting higher-order topology with explicit lattice model constructions.

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Hao-Ran Zhang, Jian-Hao Zhang, Zheng-Cheng Gu, Rui-Xing Zhang, Shuo Yang. 2022-12-26. Intrinsically Interacting Higher-Order Topological Superconductors. https://doi.org/10.1103/physrevb.108.l060504

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