Magnetic Proximity Effect in a van der Waals Moiré Superlattice

Abstract

We investigate the magnetic proximity effect in a van der Waals heterostructure formed by a monolayer semiconductor stacked on a two-dimensional (2D) ferromagnet, where the lattice mismatch and twisting between the layers typically lead to the formation of a moiré pattern. We find that the magnetic proximity effect arising from the spin-dependent interlayer coupling depends sensitively on the interlayer atomic registry. Consequently, in the moiré pattern, the spatial variation of the atomic registry leads to a lateral modulation of a magnetic proximity field. Such a moiré modulated magnetic proximity effect manifests as a miniband spin splitting that strongly depends on the moiré periodicity, which can be mechanically tuned by a relative twisting and/or strain between the layers. We also show, because of the moiré modulation on the interlayer distance, a perpendicular electric field can be used to control the miniband spin splitting. Our results suggest potential nanodevices where the moiré modulated magnetic proximity effect can lead to unique spin controllability.