Electronic properties of twisted multilayer graphene

Abstract

Twisted bilayer graphene displays many fascinating properties that can be tuned by varying the relative angle (also called twist angle) between its layers. As a notable feature, both the electronic flat bands and the corresponding strong electron localization have been obtained at a specific ‘magic’ angle ( ∼1.1∘ ), leading to the observation of several strongly correlated electronic phenomena. Such a discovery has hence inspired the creation of a novel research field called twistronics, i.e. aiming to explore novel physical properties in vertically stacked 2D structures when tuning the twist angle between the related layers. In this paper, a comprehensive and systematic study related to the electronic properties of twisted multilayer graphene (TMG) is presented based on atomistic calculations. The dependence of both the global and the local electronic quantities on the twist angle and on the stacking configuration are analyzed, fully taking into account atomic reconstruction effects. Consequently, the correlation between structural and electronic properties are clarified, thereby highlighting the shared characteristics and differences between various TMG systems as well as providing a comprehensive and essential overview. On the basis of these investigations, possibilities to tune the electronic properties are discussed, allowing for further developments in the field of twistronics.