High-Pressure-Induced Transition from Ferromagnetic Semiconductor to Spin Gapless Semiconductor in Quaternary Heusler Alloy VFeScZ (Z = Sb, As, P)

Abstract

In this paper, the structure and the electronic and magnetic properties of VFeScZ (Z = Sb, As, P) series alloys are systematically studied based on the Perdew−Burke−Ernzerhof (PBE) generalized gradient approximation (GGA) calculation within the first-principles density functional theory. The results showed that VFeScSb and VFeScP are ferromagnetic semiconductors and VFeScAs exhibits half-metallic ferromagnetism under zero pressure. As the pressure increases, the narrow indirect gap of VFeScZ (Z = Sb, As, P) alloy gradually decreases, and gets close to zero, leading to spin gapless semiconductor (SGS) transition. The pressure phase transition point of VFeScSb, VFeScAs, and VFeScP alloy is 132 GPa, 58 GPa, and 32 GPa, respectively. As a result, the pressure effect provides an opportunity to tune the electronic properties of the alloys by external pressure. The present findings provide a technical method for us to actually use the Heusler alloy SGS.

Keywords

• Heusler alloy
• spin gapless semiconductor
• magnetism
• pressure