Progress on band structure engineering of twisted bilayer and two-dimensional moir\'e heterostructures

TL;DR

This paper reviews recent progress in engineering the electronic band structures of twisted bilayer and heterostructure 2D materials, highlighting new quantum states and the effects of stacking and twisting.

Contribution

It provides a comprehensive review of how stacking and twisting in van der Waals heterostructures modify electronic properties and introduces future research directions.

Findings

Discovery of novel quantum states in graphene/hBN heterostructures

Analysis of band structure modifications due to stacking and twisting

Perspectives on expanding the 2D material phase library

Abstract

Artificially constructed van der Waals heterostructures (vdWHs) provide an ideal platform for realizing emerging quantum phenomena in condensed matter physics. Two methods for building vdWHs have been developed: stacking two-dimensional (2D) materials into a bilayer structure with different lattice constants, or with different orientations. The interlayer coupling stemming from commensurate or incommensurate superlattice pattern plays an important role in vdWHs for modulating the band structures and generating new electronic states. In this article, we review a series of novel quantum states discovered in two model vdWH systems -- graphene/hexagonal boron nitride (hBN) hetero-bilayer and twisted bilayer graphene (tBLG), and discuss how the electronic structures are modified by such stacking and twisting. We also provide perspectives for future studies on hetero-bilayer materials, from which an expansion of 2D material phase library is expected.