Enhanced Curie temperature and skyrmion stability in room temperature ferromagnetic semiconductor CrISe monolayer

TL;DR

This paper reports CrISe monolayer as a room temperature ferromagnetic semiconductor with enhanced Curie temperature and stable skyrmions, highlighting its potential for next-generation spintronic devices.

Contribution

The study introduces CrISe monolayer as a new room temperature ferromagnetic semiconductor with tunable magnetic properties and stable skyrmions driven by large Dzyaloshinskii-Moriya interaction.

Findings

Curie temperature of 322 K, enhanced to 385 K with strain

Stable sub-10 nm skyrmions at room temperature

Large DMI of 2.40 meV due to broken inversion symmetry

Abstract

We report CrISe monolayer as a room temperature ferromagnetic semiconductor with the Curie temperature ($T_C$), magnetic anisotropy energy (MAE) and band gap being 322 K, 113 $\mu$eV and 0.67 eV, respectively. The $T_C$ and MAE can be further enhanced up to 385 K and 313 $\mu$eV by tensile strain. More interestingly, the magnetic easy axis can be switched between off-plane and in-plane by compressive strain. Particularly, due to the broken inversion symmetry and strong spin-orbit coupling of Se atoms, a large Dzyaloshinskii-Moriya interaction (DMI) of 2.40 meV is obtained. More importantly, by micromagnetic simulations, stable skyrmions with sub-10 nm radius are stabilized by the large DMI above room temperature in a wide range of strain from $-2\%$ to $6\%$. Our work demonstrates CrISe as a promising candidate for next-generation skyrmion-based information storage devices and provides guidance for the research of DMI and skyrmions in room temperature ferromagnetic semiconductors.