A strategic high throughput search for identifying stable Li based half Heusler alloys for spintronics applications

TL;DR

This study employs high throughput DFT calculations to identify stable, magnetic, and spin-polarized Li-based half Heusler alloys suitable for spintronics, revealing 26 stable compositions with promising magnetic properties.

Contribution

The paper introduces a systematic high throughput computational approach to discover stable and magnetic Li-based half Heusler alloys for spintronics applications, identifying 26 promising candidates.

Findings

26 dynamically stable magnetic compositions identified

10 ferromagnetic and 12 ferrimagnetic alloys with 100% spin polarization

Several alloys exhibit tetragonal distortion indicating potential magnetocrystalline anisotropy

Abstract

In this work, high throughput DFT calculations are performed on the alkali metal-based half Heusler alloys; LiY$_p$Y$^\prime_{1-p}$S (Y, Y$^\prime$ = V, Cr, Mn, Fe, Co, Ni and $\mathit{p}$ = 0, 0.25, 0.5, 0.75, 1). Starting with 243 structural replica, systematic filters are designed to select the energetically and vibrationally favorable compositions by considering the contributions stemming from the magnetic alignments of the ions. Thereby, 26 dynamically stable magnetic compositions are identified, of which 10 are found to be ferromagnetic (FM), 4 antiferromagnetic (AFM) and 12 ferrimagnetic (FiM). 4 FM and 8 FiM ones are found to show 100 $\%$ spin polarization. Further, tetragonal distortion is found to be present in 4 FM, 3 FiM and 4 AFM compositions, which indicates the possibility of easy-axis magnetocrystalline anisotropy. The ferromagnetic LiFe$_{0.5}$Mn$_{0.5}$S and antiferromagnetic LiFeS are found to have the most prominent easy-axis magnetocrystalline anisotropy.