First-principles studies of spin-phonon coupling in Cr2Ge2Te6 monolayer

TL;DR

This study uses first-principles calculations to analyze spin-phonon coupling in Cr2Ge2Te6 monolayer, revealing significant coupling in specific phonon modes and enhancement under strain, informing spintronic material design.

Contribution

It provides the first detailed analysis of spin-phonon coupling in Cr2Ge2Te6 monolayer, highlighting the impact of specific phonon modes and strain on coupling strength.

Findings

Eg phonon mode at 211.8 cm^{-1} exhibits strong SPC of 3.19 cm^{-1}

In-plane compressive strain enhances SPC in the monolayer

Insights into SPC mechanisms in 2D magnetic semiconductors

Abstract

We perform systematic first-principles calculations to investigate the spin-phonon coupling (SPC) of Cr2Ge2Te6 (CGT) monolayer (ML). It is found that the Eg phonon mode at 211.8 cm^{-1} may have a SPC as large as 3.19 cm^{-1}, as it directly alters the superexchange interaction along the Cr-Te-Cr pathway. Furthermore, the strength of SPC of the CGT ML can be further enhanced by an in-plane compressive strain. These results provide useful insights for the understanding of SPC in novel two-dimensional magnetic semiconductors and may guide the design of spintronic and spin Seebeck materials and devices.