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arXiv · 2109.11151

Metal-Insulator transition in strained Graphene: A quantum Monte carlo study

Lufeng Zhang·Chi Ma·Tianxing Ma
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Abstract

Motivated by the possibility of a strain tuning effect on electronic properties of graphene, the semimetal-Mott insulator transition process on the uniaxial honeycomb lattice is numerically studied using Determinant Quantum Monte Carlo. As our simulations are based on the half-filled repulsive Hubbard model, the system is sign problem free. Herein, the temperature-dependent DC conductivity is used to characterize electronic transport properties. The data suggest that metallic is suppressed in the presence of strain. More interestingly, within the finite-size scaling study, a novel antiferromagnetic phase arises at around $U\sim U_{c}$. Therefore, a phase diagram generated by the competition between interactions and strain is established, which may help to expand the application of strain effect on graphene.

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Lufeng Zhang, Chi Ma, Tianxing Ma. 2021-09-23. Metal-Insulator transition in strained Graphene: A quantum Monte carlo study. https://doi.org/10.1002/pssr.202100287

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