Magnetic Interactions and Electronic Structure of Pt$_{2}$Mn$_{1-x}$Y$_{x}$Ga (Y = Cr and Fe) system : An ab-initio calculation

TL;DR

This study uses ab-initio calculations to explore how substituting Mn with Fe or Cr in Pt2MnGa affects its electronic and magnetic properties, revealing ferromagnetic and anti-ferromagnetic ground states respectively.

Contribution

It provides new insights into the magnetic interactions and electronic structures of Pt2MnGa-based alloys with Fe and Cr substitutions, predicting their stability and magnetic configurations.

Findings

Fe substitution induces ferromagnetism.

Cr substitution favors anti-ferromagnetic configuration.

Alloy remains electronically stable with substitutions.

Abstract

First principles density functional theory based calculations have been carried out to predict the effects of Mn replacement by Fe and Cr on electronic as well as magnetic properties of Pt$_{2}$MnGa as well as Ni$_{2}$MnGa. All the materials studied here are predicted to have conventional Heusler alloy structure in their ground state and they are found to be electronically stable on the basis of their respective formation energy. The replacement of Mn by Fe leads to a ferromagnetic ground state whereas in case of Mn replacement by Cr an {\it intra-sublattice} anti-ferromagnetic configuration has been observed to have lower energy. We study the magnetic exchange interaction between the atoms for the materials with ferromagnetic and anti-ferromagnetic configurations to show the effects of Fe and Cr substitution at Mn site on the magnetic interactions of these systems. Detailed analysis of electronic structure in terms of density of states has been carried out to study the effect of substitution.