Switchable magnetic phases in CrSBr$_{1-x}$Cl$_x$ and CrSBr/CrSCl heterostructures

TL;DR

This study explores how chemical substitution, strain, and stacking influence magnetism in 2D CrSBr/CrSCl materials, revealing switchable magnetic phases and interfacial ferromagnetism with potential for magnetic control.

Contribution

It demonstrates the ability to reversibly switch magnetic phases in bilayers and heterostructures, and uncovers interfacial ferromagnetism induced by proximity effects.

Findings

Cl induces competing magnetic couplings leading to spin-glass states.

Strain can reversibly switch interlayer magnetic order.

Interfacial ferromagnetism stabilizes in-plane magnetization in heterostructures.

Abstract

Strategies such as chemical substitution, strain engineering and van der Waals stacking offer powerful means to control magnetism in 2D materials, enabling the emergence of novel quantum phenomena. Here, we investigate the magnetic properties of bulk CrSBr$_{1-x}$Cl$_x$ ($x = 0{-}1$) and the strain-dependent switchable magnetic phases in bilayers CrSBr, CrSCl, and CrSBr/CrSCl heterostructures, using firstprinciples calculations. Our findings demonstrate that Cl incorporation in CrSBr induces competing interlayer antiferromagnetic and ferromagnetic couplings, leading to a spin-glass state when the Cl content exceeds a 67%. This is accompanied by a decrease of magnetic anisotropy, where a $XY$-type magnetic ground state is observed in pristine CrSCl. For CrSBr and CrSCl bilayers, we report a reversible strain-induced switching between interlayer antiferromagnetic and ferromagnetic configurations. Furthermore, we reveal the emergence of interfacial ferromagnetism in CrSBr/CrSCl heterostructures, stabilizing an in-plane magnetization axis for CrSCl by proximity to CrSBr. These results underscore the potential of manipulating magnetism in 2D magnetic materials through precise control of magnetic phases.