Experimental evidence for orbital magnetic moments generated by moiré-scale current loops in twisted bilayer graphene

Abstract

One of the most remarkable properties of magic-angle twisted bilayer graphene is that the low-energy bands can have nonzero valley Chern numbers, which enable the realization of the first example of a material with purely orbital-based magnetism. In this work, evidence for orbital magnetic moment generated by the moir\'e-scale current loops circulating in the moir\'e pattern of a twisted bilayer graphene is reported. This paves the way to explore orbital magnetism in slightly twisted graphene systems.