Relativity and Magnetism in Ni-Pd and Ni-Pt Alloys

TL;DR

This paper demonstrates that relativistic effects are crucial in explaining the contrasting magnetic behaviors of Ni-Pd and Ni-Pt alloys, affecting their electronic structure and local magnetic moments.

Contribution

It provides a detailed analysis showing how relativity influences the electronic and magnetic properties of Ni-Pd and Ni-Pt alloys, a novel insight into alloy magnetism.

Findings

Ni magnetic moment increases with Pd addition only when relativity is considered.

Ni magnetic moment decreases with Pt addition only when relativity is considered.

Relativity affects spin-polarized densities and band center splitting in the alloys.

Abstract

We show that the differences in the magnetic properties of Ni-Pd and Ni-Pt alloys arise mainly due to relativity. In particular, we find that the local magnetic moment of Ni increases with the addition of Pd in Ni-Pd while it decreases with the addition of Pt in Ni-Pt, as found experimentally, only if relativity is present. Our analysis is based on the effects of relativity on (i) the spin-polarized densities of states of Ni, (ii) the splitting of majority and minority spin d-band centers of Ni, and (iii) the separation between s-d band centers of Pd and Pt in Ni-Pd and Ni-Pt alloys.