Controllable high Curie temperature through 5d transition metal atom doping in CrI3

Abstract

Two-dimensional (2D) CrI3 is a ferromagnetic semiconductor with potential for applications in spintronics. However, its low Curie temperature (T c) hinders realistic applications of CrI3. Based on first-principles calculations, 5d transition metal (TM) atom doping of CrI3 (TM@CrI3) is a universally effective way to increase T c, which stems from the increased magnetic moment induced by doping with TM atoms. T c of W@CrI3 reaches 254 K, nearly six times higher than that of the host CrI3. When the doping concentration of W atoms is increased to above 5.9%, W@CrI3 shows room-temperature ferromagnetism. Intriguingly, the large magnetic anisotropy energy of W@CrI3 can stabilize the long-range ferromagnetic order. Moreover, TM@CrI3 has a strong ferromagnetic stability. All TM@CrI3 change from a semiconductor to a half-metal, except doping with Au atom. These results provide information relevant to potential applications of CrI3 monolayers in spintronics.