A new twist in graphene research: Twisted graphene

Graphene is perhaps the most studied material around the globe in recent years. It has served as a classic example of 2D material not just because of the historical reasons, but importantly, due to distinctly observable dimensional crossover in it, from 2D to 3D, via Bernal stacked (AB) bilayer to multilayer finally culminating in graphite. The interlayer interactions that are thus responsible, however, tend to differ vastly in presence of defects or disorders. Of particular interest is the angular disorder causing the layers to stack in a manner away from the conventional AB packing. The new class of graphene systems involving an angular twist among otherwise highly crystalline 2D layers, is often termed as twisted graphene. Among these, twisted bilayer graphene, tBLG, has become archetypical. The twist as a new degree of freedom induces several angle dependent properties in tBLG, from visible absorption to superconductivity, unheard of in the case of graphene itself. This article overviews the recent developments in twisted graphene covering aspects related to its synthesis, the twist dependent properties and potential applications. (C) 2019 Elsevier Ltd. All rights reserved.