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

TL;DR

This study uses quantum Monte Carlo simulations to explore how uniaxial strain influences the metal-insulator transition in graphene, revealing a strain-induced suppression of metallic behavior and the emergence of an antiferromagnetic phase.

Contribution

It provides the first detailed phase diagram of strain and interaction effects on the metal-insulator transition in graphene using sign-problem-free quantum Monte Carlo methods.

Findings

Strain suppresses metallic conductivity in graphene.

A novel antiferromagnetic phase appears near the critical interaction strength.

A phase diagram illustrating the interplay of strain and electron interactions.

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.