Robust half-metallic ferromagnet of cubic VGe3Si4

TL;DR

This study predicts that cubic VGe3Si4 is a stable, half-metallic ferromagnet with a significant gap, suitable for spintronic applications, based on advanced density functional theory calculations.

Contribution

It introduces cubic VGe3Si4 as a new half-metallic ferromagnet with confirmed stability and electronic properties through state-of-the-art computational methods.

Findings

Cubic VGe3Si4 is a half-metallic ferromagnet with a 350 meV gap.

The structure is stable against deformations.

It is robust against antiferromagnetic fluctuations.

Abstract

To seek half-metallic ferromagnets compatible with the GeSi semiconductor, we use state-of-the-art density-functional-theory methods to study cubic $\mathrm{VGe_3Si_4}$. After optimizing its crystal structure with various magnetic orders considered, we find the ferromagnetic structure is the ground state phase and investigate its stability, and then study its spin-resolved electronic structure with an improved method. Our calculated results show that the cubic $\mathrm{VGe_3Si_4}$ is a half-metallic ferromagnet with half-metallic gap 350 meV, and it is structurally stable against deformations and magnetically robust against antiferromagnetic fluctuations. These results make us believe that the cubic $\mathrm{VGe_3Si_4}$ could be synthesized as good thin films soon and used in practical spintronic devices.