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arXiv · 2209.03628

Transport anisotropy and metal-insulator transition in striped Dirac fermion systems

Jingyao Meng·Runyu Ma·Lufeng Zhang·Tianxing Ma
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Abstract

Using the determinant quantum Monte Carlo method, we investigate the metal-insulator transitions induced by the stripe of charge density in an interacting two-dimensional Dirac fermion system. The stripe will introduce the transport anisotropy and insulating intermediate phase into the system, accompanied by the change of band structure and a peak of density of states around Fermi energy. In the case of strong correlation, stripe exhibits competition with Coulomb repulsion through closing the energy gap and disrupting the magnetic order, and finally drives the system in Mott insulating phase back to the metallic state. Our results may provide a feasible way to modify transport properties by setting charge stripes in experiments.

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Jingyao Meng, Runyu Ma, Lufeng Zhang, Tianxing Ma. 2022-09-08. Transport anisotropy and metal-insulator transition in striped Dirac fermion systems. https://doi.org/10.1103/physrevb.106.235140

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