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arXiv · 2012.15657

Real-space construction of crystalline topological superconductors and insulators in 2D interacting fermionic systems

Jian-Hao Zhang·Shuo Yang·Yang Qi·Zheng-Cheng Gu
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Abstract

The construction and classification of crystalline symmetry protected topological (SPT) phases in interacting bosonic and fermionic systems have been intensively studied in the past few years. Crystalline SPT phases are not only of conceptual importance, but also provide great opportunities towards experimental realization since space group symmetries naturally exist for any realistic material. In this paper, we systematically classify the crystalline topological superconductors (TSC) and topological insulators (TI) in 2D interacting fermionic systems by using an explicit real-space construction. In particular, we discover an intriguing fermionic crystalline topological superconductor that can only be realized in interacting fermionic systems (i.e., not in free-fermion or bosonic SPT systems). Moreover, we also verify the recently conjectured crystalline equivalence principle for generic 2D interacting fermionic systems.

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Jian-Hao Zhang, Shuo Yang, Yang Qi, Zheng-Cheng Gu. 2020-12-31. Real-space construction of crystalline topological superconductors and insulators in 2D interacting fermionic systems. https://doi.org/10.1103/physrevresearch.4.033081

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