  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.
