Topological charge pumping in twisted bilayer graphene
Yinhan Zhang, Yang Gao, Di Xiao
Abstract
We show that a sliding motion between the two layers of a moir\'e superlattice induces an electric current and realizes a two-dimensional version of the topological Thouless pump when the Fermi energy lies in one of the minigaps. Interestingly, a chiral charge pump, namely, a transverse current induced by the sliding motion, is possible in twisted homobilayers. This result is confirmed by a concrete calculation of the adiabatic current in twisted bilayer graphene. Our work reveals an interesting link between mechanical motion and electricity unique to moir\'e superlattices, and may find applications in nanogenerators and nanomotors.
Topics & Concepts
SuperlatticeGrapheneCondensed matter physicsBilayer grapheneCharge (physics)Adiabatic processCurrent (fluid)Fermi energyTopology (electrical circuits)PhysicsMaterials scienceNanotechnologyQuantum mechanicsElectronThermodynamicsMathematicsCombinatoricsGraphene research and applicationsQuantum and electron transport phenomenaMechanical and Optical Resonators