摘要
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 Cmca and R3m structures which have negative formation enthalpy and stable phonon dispersion at ambient pressure.The Cmca structure is a layered antiferromagnetic metal.The cleaved energy of a single layer is 0.464 J/m^(2),indicating the possible synthesis of CrTe monolayer.The R3m structure is a ferromagnetic half-metal.When external pressure is applied,the ground-state structure of CrTe transitions from P63/mmc structure to R3m structure at a pressure of 34 GPa,then to Fm3m structure at 42 GPa.We thought these results help to motivate experimental studies of the CrTe compounds in the application of spintronics.
基金
This work was supported by the National Natural Science Foundation of China(Nos.11904312 and 11904313),the Project of Hebei Educational Department,China(Nos.ZD2018015 and QN2018012),the Natural Science Foundation of Hebei Province of China(No.A2020203027),the Doctor Foundation Project of Yanshan University(No.BL19008),and the Scientific Research Foundation of the Higher Education of Hebei Province,China(No.BJ2020015).The numerical calculations in this paper have been done on the supercomputing system in the High Performance Computing Center of Yanshan University.
