Itinerant spin polaron and metallic ferromagnetism in semiconductor moiré superlattices

Abstract

Itinerant spin polaron and metallic ferromagnetism are theoretically predicted in the Mott insulator in semiconductor moir\'e superlattices doped below and above half filling of the narrow moir\'e band, respectively. The existence of a spin polaron can be directly identified from the kink in the dependence of the charge gap on the magnetic field.