High throughput screening for spin-gapless semiconductors in quaternary Heusler compounds

TL;DR

This study uses high throughput density functional theory to systematically identify 70 stable spin-gapless semiconductors in quaternary Heusler alloys, revealing their electronic properties and potential for spintronic applications.

Contribution

It presents the first large-scale screening of SGSs in quaternary Heusler compounds, identifying stable candidates and analyzing their electronic and transport properties.

Findings

Identified 70 stable SGSs in quaternary Heusler alloys.

Demonstrated all four types of SGSs based on band spin characters.

Found promising transport properties in type-II SGSs for spintronics.

Abstract

Based on high throughput density functional theory calculations, we performed systematic screening for spin-gapless semiconductors (SGSs) in quaternary Heusler alloys XX 0 YZ (X, X 0 , and Y are transition metal elements without Tc, and Z is one of B, Al, Ga, In, Si, Ge, Sn, Pb, P, As, Sb, and Bi). Following the empirical rule, we focused on compounds with 21, 26, or 28 valence electrons, resulting in 12, 000 possible chemical compositions. After systematically evaluating the thermodynamic, mechanical, and dynamical stabilities, we successfully identified 70 stable SGSs, confirmed by explicit electronic structure calculations with proper magnetic ground states. It is demonstrated that all four types of SGSs can be realized, defined based on the spin characters of the bands around the Fermi energy, and the type-II SGSs show promising transport properties for spintronic applications. The effect of spin-orbit coupling is investigated, resulting in large anisotropic magnetoresistance and anomalous Nernst effects.