Magnetoresistance in an ultrathin Bi2Se3 film between two ferromagnetic insulators

Abstract

We theoretically investigate the magnetoresistance effect of an ultrathin Bi2Se3 film sandwiched between two ferromagnetic insulators (FIs). It is found that the conductance is quantized to be e2/h and vanishing, respectively, for parallel and antiparallel magnetization configurations of the two FIs, which stems from a transition of the Bi2Se3 film from the quantum anomalous Hall phase to a conventional insulator. This quantum magnetoresistance is robust against disorder scattering.