Impacts of in-plane strain on commensurate graphene/hexagonal boron nitride superlattices

TL;DR

This study uses ab initio calculations to explore how in-plane strain affects the electronic properties of graphene/hBN heterostructures, revealing significant band structure modifications and transport efficiency changes.

Contribution

It provides new insights into strain-induced electronic property modifications in G/hBN, especially regarding moiré patterns and transport directions, based on detailed ab initio analysis.

Findings

Strain causes valley drifts and band gap modulation.

Moiré patterns are significantly affected by in-plane strain.

Zigzag direction enhances electronic transport under non-equibiaxial strain.

Abstract

Due to atomically thin structure, graphene/hexagonal boron nitride (G/hBN) heterostructures are intensively sensitive to the external mechanical forces and deformations being applied to their lattice structure. In particular, strain can lead to the modification of the electronic properties of G/hBN. Furthermore, moir\'e structures driven by misalignment of graphene and hBN layers introduce new features to the electronic behavior of G/hBN. Utilizing {\it ab initio} calculation, we study the strain-induced modification of the electronic properties of diverse stacking faults of G/hBN when applying in-plane strain on both layers, simultaneously. We observe that the interplay of few percent magnitude in-plane strain and moir\'e pattern in the experimentally applicable systems leads to considerable valley drifts, band gap modulation and enhancement of the substrate-induced Fermi velocity renormalization. Furthermore, we find that regardless of the strain alignment, the zigzag direction becomes more efficient for electronic transport, when applying in-plane non-equibiaxial strains.