Electronic structure and magnetism in transition metal doped InSe monolayer: A GGA plus U study

The electronic structures and magnetic properties of X-doped (X = Ni, Pd, Pt) InSe monolayers were investigated using first-principles calculations based on the GGA + U method. We show that the chemical doping is easier to take place at Se-rich than In-rich environment, and that Pt substitution of In is energetically most favorable among the three types of doping, followed by Ni and Pd. We further conduct calculation of ground state and band structures of Ni-, Pd- and Pt-doped InSe monolayers and find that the doped systems show diluted magnetic semiconducting nature. The magnetic moments of the X-doped systems are dominantly originated from the X dopants, and their extent of spin density expansion to the neighboring atoms is stronger in Pd- and Pt-doped cases than Ni-doped case. Further analysis of the impurity states near the Fermi energy reveals a strong spin-polarization feature in the three doped systems. Our results demonstrate that substitutional doping with Ni, Pd and Pt in InSe monolayer represents an effective manner to modulate electronic and magnetic properties of InSe for spintronic applications.