Electrical Control of Carriers Spin Orientation in FeVTiSi Heusler Alloy

TL;DR

This paper proposes a new quaternary Heusler alloy, FeVTiSi, which can conduct spin-polarized currents with electrically tunable spin orientation at room temperature, promising for spintronic applications.

Contribution

It introduces FeVTiSi as an intrinsic bipolar magnetic semiconductor with high Curie temperature, enabling electric control of spin polarization in spintronic devices.

Findings

FeVTiSi is an intrinsic bipolar magnetic semiconductor.

It can conduct fully spin-polarized currents with tunable spin direction.

The alloy has a Curie temperature of 1293 K, well above room temperature.

Abstract

The direct control of carriers spin by electric field under room temperature is one of the most important challenges in the field of spintronics. For this purpose, we here propose a quaternary Heusler alloy FeVTiSi. Based on first principles calculations, FeVTiSi alloy is found to be an intrinsic bipolar magnetic semiconductor in which the valence band and conduction band approach the Fermi level through opposite spin channels. Thus FeVTiSi alloy can conduct completely spin-polarized currents with tunable spin-polarization direction simply by applying a gate voltage. Furthermore, by Monte Carlo simulations based on the classical Heisenberg Hamiltonian, the Curie temperature of FeVTiSi alloy is predicted to be as high as 1293 K, far above the room temperature. The bipolar magnetic semiconducting character and the high Curie temperature endow the FeVTiSi alloy great potentials in developing electrically controllable spintronic devices working at room temperature.