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arXiv · 1708.03538

Nature of continuous phase transitions in interacting topological insulators

Tian-Sheng Zeng·W. Zhu·Jian-Xin Zhu·D. N. Sheng
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Abstract

We revisit the effects of the Hubbard repulsion on quantum spin Hall effects (QSHE) in two-dimensional quantum lattice models. We present both unbiased exact diagonalization and density-matrix renormalization group simulations with numerical evidences for a continuous quantum phase transition (CQPT) separating QSHE from the topologically trivial antiferromagnetic phase. Our numerical results suggest that, the nature of CQPT exhibits distinct finite-size scaling behaviors, which may be consistent with either Ising or XY universality classes for different time-reversal symmetric QSHE systems.

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Tian-Sheng Zeng, W. Zhu, Jian-Xin Zhu, D. N. Sheng. 2017-11-09. Nature of continuous phase transitions in interacting topological insulators. https://doi.org/10.1103/physrevb.96.195118

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