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arXiv · 1909.03025

Combined spontaneous symmetry-breaking and symmetry-protected topological order from cluster charge interaction

Chen Peng·Rong-Qiang He·Yuan-Yao He·Zhong-Yi Lu
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Abstract

The study of symmetry-protected topological states in presence of electron correlations has recently aroused great interest as rich and exotic phenomena can emerge. Here, we report a concrete example by employing large-scale unbiased quantum Monte Carlo study of the Kane-Mele model with cluster charge interactions. The ground-state phase diagram for the model at half filling is established. Our simulation identifies the coexistence of a symmetry-protected topological order with a symmetry-breaking Kekul$\acute{e}$ valence bond order and shows that the spontaneous symmetry-breaking is accompanied by an interaction-driven topological phase transition (TPT). This TPT features appearance of zeros of single-particle Green's function and gap closing in spin channel rather than single-particle excitation spectrum, and thus has no mean-field correspondence.

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Chen Peng, Rong-Qiang He, Yuan-Yao He, Zhong-Yi Lu. 2019-09-06. Combined spontaneous symmetry-breaking and symmetry-protected topological order from cluster charge interaction. https://doi.org/10.1103/physrevresearch.2.033291

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