Biaxial-stress-driven full spin polarization in ferromagnetic hexagonal chromium telluride

TL;DR

This study demonstrates that applying biaxial tensile stress to hexagonal chromium telluride induces full spin polarization, making it a promising stable and easily fabricated material for spintronic applications.

Contribution

It reveals that biaxial stress can induce full spin polarization in CrTe, a novel approach for designing stable spintronic materials.

Findings

Full spin polarization achieved at 6.0% in-plane strain.

Ferromagnetic order stabilized against antiferromagnetic fluctuations.

Half-metallic ferromagnetism at 4.8% strain.

Abstract

It is important to spintronics to achieve fully-spin-polarized magnetic materials that are stable and can be easily fabricated. Here, through systematical density-functional-theory investigations, we achieve high and even full spin polarization for carriers in the ground-state phase of CrTe by applying tensile biaxial stress. The resulting strain is tensile in the xy plane and compressive in the z axis. With the in-plane tensile strain increasing, the ferromagnetic order is stable against antiferromagnetic fluctuations, and a half-metallic ferromagnetism is achieved at an in-plane strain of 4.8%. With the spin-orbit coupling taken into account, the spin polarization is equivalent to 97% at the electronic phase transition point, and then becomes 100.0% at the in-plane strain of 6.0%. These make us believe that the full-spin-polarized ferromagnetism in this stable and easily-realizable hexagonal phase could be realized soon, and applied in spintronics.