# Spin reorientation and controllable magnetic anisotropy in two-dimensional MnSe2/As van der Waals heterostructures

## TL;DR

This paper shows how combining MnSe2 and As layers can control magnetic properties in 2D materials, which could help in developing spintronic devices.

## Contribution

The study introduces a new method to control magnetic anisotropy in 2D heterostructures using interfacial electric fields and structural parameters.

## Key findings

- Interfacial coupling in MnSe2/As heterostructures causes spin reorientation from in-plane to out-of-plane magnetization.
- Magnetic anisotropy energy is tunable via electric fields, interlayer distance, and As-layer thickness.
- PMA enhancement is mainly due to changes in Se-p orbital electronic states.

## Abstract

First-principles calculations demonstrate that interfacial coupling in MnSe2/As van der Waals heterostructures induces spin reorientation, switching the easy-magnetization axis of the MnSe2 monolayer from in-plane to out-of-plane. Interlayer charge transfer generates a built-in electric field directed from the As layer toward MnSe2, which drives this spin reorientation. The magnetocrystalline anisotropy energy (MAE) is found to be broadly tunable via external electric fields, interlayer distance variation, and thickness of the As layer. Crucially, perpendicular magnetic anisotropy (PMA) enhancement is achieved via applied electric fields and reduced interlayer spacing. Atomic-resolved MAE and orbital-resolved MAE analysis combined with density of states calculations reveal that the PMA enhancement primarily originates from modified electronic states of Se-p orbitals. This work establishes a viable strategy for tailoring 2D magnetic properties and may be helpful for preparing 2D spintronic devices.

•The MnSe2/As heterostructure exhibits high-TC ferromagnetism and strong PMA•Built-in electric field induces spin reorientation, shifting anisotropy from IMA to PMA•MAE is tunable via electric field, interlayer distance, and As-layer thickness•PMA enhancement primarily originates from modified electronic states of Se-p orbitals

The MnSe2/As heterostructure exhibits high-TC ferromagnetism and strong PMA

Built-in electric field induces spin reorientation, shifting anisotropy from IMA to PMA

MAE is tunable via electric field, interlayer distance, and As-layer thickness

PMA enhancement primarily originates from modified electronic states of Se-p orbitals

Physics; Nanoscience