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arXiv · 1904.05504

Intermediate Phase in Interacting Dirac Fermions with Staggered Potential

Jingyao Wang·Lufeng Zhang·Runyu Ma·Qiaoni Chen·Ying Liang·Tianxing Ma
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Abstract

By performing exact quantum Monte Carlo simulations of a model of interacting Dirac Fermions with staggered potential, we reveal a novel intermediate phase where the electronic correlations drive a band insulator metallic, and at a larger interaction, drive the metal to Mott insulator. We also show that the Mott insulating phase is antiferromagnetic. A complete phase diagram is achieved by studying the phase transitions at large staggered potential and interaction strengths, which shows that the intermediate state is robust and occupies a large part of the phase diagram and that it should be more feasible to be detected experimentally.

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Jingyao Wang, Lufeng Zhang, Runyu Ma, Qiaoni Chen, Ying Liang, Tianxing Ma. 2019-04-11. Intermediate Phase in Interacting Dirac Fermions with Staggered Potential. https://doi.org/10.1103/physrevb.101.245161

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