Diverse magnetism in stable and metastable structures of CrTe

In this paper, we systematically investigated the structural and magnetic properties of CrTe by combining particle swarm optimization algorithm and first-principles calculations. By considering the electronic correlation effect, we predicted the ground-state structure of CrTe to be NiAs-type (space group P6₃/mmc) structure at ambient pressure, consistent with the experimental observation. Moreover, we found two extra meta-stable Cmcaand R\overline{3}m structures which have negative formation enthalpy and stable phonon dispersion at ambient pressure. The Cmcastructure is a layered antiferromagnetic metal. The cleaved energy of a single layer is 0.464 J/m² , indicating the possible synthesis of CrTe monolayer. The R\overline{3}m structure is a ferromagnetic half-metal. When external pressure is applied, the ground-state structure of CrTe transitions from P63/mmc structure to R\overline{3}m structure at a pressure of 34 GPa, then to R\overline{3}m structure at 42 GPa. We thought these results help to motivate experimental studies of the CrTe compounds in the application of spintronics.