Magnon straintronics in the 2D van der Waals ferromagnet CrSBr from first-principles

TL;DR

This paper explores how mechanical strain can be used to control magnetic properties and magnon dynamics in the 2D ferromagnetic semiconductor CrSBr, highlighting its potential for strain-tunable magnonic devices.

Contribution

It provides a first-principles analysis of strain effects on magnetic order and magnon behavior in CrSBr, revealing strain-driven enhancements of Curie temperature and directional magnon control.

Findings

Magnon dynamics can be selectively modified by strain along crystallographic directions.

Strain can increase the Curie temperature by approximately 30%.

The study demonstrates potential for strain-controlled magnonic applications in 2D materials.

Abstract

The recent isolation of two-dimensional (2D) magnets offers tantalizing opportunities for spintronics and magnonics at the limit of miniaturization. One of the key advantages of atomically-thin materials is their outstanding deformation capacity, which provides an exciting avenue to control their properties by strain engineering. Herein, we investigate the magnetic properties, magnon dispersion and spin dynamics of the air-stable 2D magnetic semiconductor CrSBr ($T_C$ = 146 K) under mechanical strain using first-principles calculations. Our results provide a deep microscopic analysis of the competing interactions that stabilize the long-range ferromagnetic order in the monolayer. We showcase that the magnon dynamics of CrSBr can be modified selectively along the two main crystallographic directions as a function of applied strain, probing the potential of this quasi-1D electronic system for magnon straintronics applications. Moreover, we predict a strain-driven enhancement of $T_C$ considering environmental screening by ~30%, allowing the propagation of spin waves at higher temperatures.