Strain-induced interlayer magnetic coupling spike of two-dimensional van der Waals material Fe$_5$GeTe$_2$

TL;DR

This study reveals that applying a 3% in-plane strain to the 2D van der Waals material Fe$_5$GeTe$_2$ causes a dramatic increase in interlayer magnetic coupling and magnetic anisotropy, with potential implications for spintronics.

Contribution

It demonstrates a strain-induced spike in interlayer magnetic coupling and magnetic anisotropy in Fe$_5$GeTe$_2$, highlighting a new method to control magnetic properties in 2D materials.

Findings

Interlayer magnetic coupling increases from 1.15 to 12.79 meV/f.u under 3% strain.

Magnetic anisotropy energy is significantly enhanced, inducing magnetic configuration transitions.

Strain effectively tunes magnetic properties in Fe$_5$GeTe$_2$ for spintronics applications.

Abstract

A stronger interlayer magnetic coupling (ILMC) can open up new opportunities in spintronics devices for Fe$_5$GeTe$_2$ (F5GT), a demonstrated two-dimensional (2D) van der Waals (vdW) material with high Currie temperature. Here we observe an extraordinary ILMC spike in F5GT, jumping from 1.15 to 12.79 meV/f.u, by applying a 3% in-plane strain. This spike is mainly ascribed to a significant increase in the magnetic moment of the Fe5 ion. Moreover, the applied in-plane strain can also significantly enhance the magnetic anisotropy energy (MAE) of the system, triggering the transition between the in/off-plane configurations in multi-layer F5GT.