A first-principle study of half-Heusler alloys CKMg and SiKMg

TL;DR

This study uses first-principle calculations to analyze the properties of half-Heusler alloys CKMg and SiKMg, revealing their potential as spintronic materials due to their half-metallic ferromagnetic behavior and high spin polarization.

Contribution

It provides the first detailed theoretical investigation of CKMg and SiKMg alloys, highlighting their half-metallicity and suitability for spintronic applications.

Findings

SiKMg is a half-metallic ferromagnet with a 1 μB magnetic moment.

CKMg is nearly half-metallic with 99.99% spin polarization.

CKMg's half-metallicity improves under low pressure.

Abstract

The structural, electronic, and magnetic properties of half-Heusler alloys CKMg and SiKMg are studied by using first-principle density functional theory. The calculations reveal the SiKMg alloy is a half-metallic ferromagnet with the magnetic moment of 1 $\mu_B$ per formula unit at equilibrium lattice constant. The magnetic moment mainly originates from the strong spin-polarization of $p$ electrons of Si atom and partial involvement of $d$ electrons of K atom. The half-metallic gap is 0.105 eV. The robustness of half-metallic against the lattice constants for SiKMg is also calculated. CKMg alloy is nearly half-metallic with a spin polarization of 99.99 \%\ at equilibrium lattice constant, but it is a good half-metallic alloy when a low pressure is applied. This shows CKMg is a very promising spintronic functional material.