Electronic structure and quantum transport in twisted bilayer graphene with resonant scatterers

Abstract

Staking layered materials revealed to be a very powerful method to tailor their electronic properties. It has indeed been theoretically and experimentally shown that twisted bilayers of graphene (tBLG) with a rotation angle $\theta$, forming Moir\'e pattern, confine electrons in a tunable way as a function of $\theta$. Here, we study electronic structure and transport in tBLG using tight-binding numerical calculations in commensurate twisted bilayer structures and a pertubative continuous theory, which is valid for not too small angles ($\theta > \sim 2^\circ $). This two approaches allow to understand the effect of $\theta$ on the local density of states, the electron lifetime due to disorder, the dc-conducitivity and the quantum correction of the conductivity due to multiple scattering effects. We distinguished the cases where disorder is equaly distributed in the two layer or only in one layer. When only one layer is disordered, diffusion properties depends strongly on $\theta$, showing thus the effect of Moir\'e electronic localisation at intermediate angles, $\sim 2^\circ < \theta < \sim 20^\circ$.