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arXiv · 1412.0092

Fermionic Symmetry Protected Topological Phase Induced by Interactions

Shang-Qiang Ning·Hong-Chen Jiang·Zheng-Xin Liu
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Abstract

Strong interactions can give rise to new fermionic symmetry protected topological phases which have no analogs in free fermion systems. As an example, we have systematically studied a spinless fermion model with $U(1)$ charge conservation and time reversal symmetry on a three-leg ladder using density-matrix renormalization group. In the non-interacting limit, there are no topological phases. Turning on interactions, we found two gapped phases. One is trivial and is adiabatically connected to a band insulator, while another one is a nontrivial symmetry protected topological phase resulting from strong interactions.

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Shang-Qiang Ning, Hong-Chen Jiang, Zheng-Xin Liu. 2015-06-12. Fermionic Symmetry Protected Topological Phase Induced by Interactions. https://doi.org/10.1103/physrevb.91.241105

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