Hybrid Wannier Chern bands in magic angle twisted bilayer graphene and the quantized anomalous Hall effect

Abstract

We propose a method for studying the strong interaction regimes in twisted bilayer graphene using hybrid Wannier functions that are Wannier-like in one direction and Bloch-like in the other. We focus on the active bands as given by the continuum model proposed by Bistritzer and MacDonald, [Proc. Natl. Acad. Sci. 108, 12233 (2011)] and discuss the properties of corresponding hybrid Wannier functions. We then employ the method for a study of the fillings of 3 electrons per moir cell using the Hartree-Fock method. We discuss at length different regimes under which a quantized anomalous Hall effect is seen in these two fillings.

Topics & Concepts