Magnetic Proximity Effect in a van der Waals Moir\'e Superlattice

TL;DR

This paper explores how moiré patterns in van der Waals heterostructures influence magnetic proximity effects, enabling tunable spin splitting through mechanical twisting, strain, and electric fields for potential nanodevice applications.

Contribution

It reveals the spatially modulated magnetic proximity effect in moiré superlattices and demonstrates control over spin splitting via twisting, strain, and electric fields.

Findings

Moiré patterns cause lateral modulation of magnetic proximity fields.

Spin splitting depends on moiré periodicity and can be mechanically tuned.

Electric fields can control miniband spin splitting via interlayer distance modulation.

Abstract

We investigate the magnetic proximity effect in van der Waals heterostructure formed by a monolayer semiconductor stacked on a 2D ferromagnet, where the lattice mismatch and twisting between the layers typically lead to the formation of moir\'e 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 moir\'e pattern, the spatial variation of the atomic registry leads to a lateral modulation of magnetic proximity field. Such moir\'e modulated magnetic proximity effect manifests as a miniband spin splitting that strongly depends on the moir\'e periodicity which can be mechanically tuned by a relative twisting and/or strain between the layers. We also show, because of the moir\'e 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 moir\'e modulated magnetic proximity effect can lead to unique spin controllability.