Influence of Ni doping on the electronic structure of Ni_2MnGa

TL;DR

This study investigates how Ni doping alters the electronic structure and magnetic properties of Ni2MnGa using computational and experimental methods, revealing changes in density of states, magnetic moments, and transition temperatures.

Contribution

It provides new insights into the effects of Ni doping on the electronic and magnetic properties of Ni2MnGa, combining theoretical calculations with photoemission spectroscopy.

Findings

Ni 3d states form due to Ni clustering

Minority-spin DOS can be tuned by Ni doping

Total magnetic moment decreases with excess Ni

Abstract

The modifications in the electronic structure of Ni_{2+x}Mn_{1-x}Ga by Ni doping have been studied using full potential linearized augmented plane wave method and ultra-violet photoemission spectroscopy. Ni 3d related electron states appear due to formation of Ni clusters. We show the possibility of changing the minority-spin DOS with Ni doping, while the majority-spin DOS remains almost unchanged. The total magnetic moment decreases with excess Ni. The total energy calculations corroborate the experimentally reported changes in the Curie temperature and the martensitic transition temperature with x.