Abstract
Despite a plethora of materials suggested for spintronic applications, a new class of materials has emerged, namely spin gapless semiconductors (SGS), which offers potentially more advantageous properties than existing ones. These magnetic semiconductors exhibit a finite band gap for one spin channel and a closed gap for the other. Here, supported by electronic-structure calculations, we report evidence of SGS behavior in equiatomic quaternary CoFeCrGa, having a cubic Heusler (prototype LiMgPdSn) structure but exhibiting chemical disorder ( structure). CoFeCrGa is found to transform from SGS to half-metallic phase under pressure, which is attributed to unique electronic-structure features. The saturation magnetization obtained at agrees with the Slater-Pauling rule and the Curie temperature is found to exceed . Carrier concentration (up to ) and electrical conductivity are observed to be nearly temperature independent, prerequisites for SGS. The anomalous Hall coefficient is estimated to be at . Considering the SGS properties and high , this material appears to be promising for spintronic applications.
1 More- Received 1 March 2015
- Revised 23 April 2015
DOI:https://doi.org/10.1103/PhysRevB.92.045201
©2015 American Physical Society