Impurity states in InSe monolayers doped with group II and IV elements

Abstract

We have used first-principles calculations to investigate the electronic structures of two-dimensional (2D) InSe monolayers doped with group II and IV elements. The results show that substituting Mg, Ca, Ge, and Sn for indium clearly modifies the electronic and magnetic properties of InSe monolayers and that these substitutions should be easily achieved in a Se-rich environment. Mg- and Ca-doped InSe monolayers develop deep acceptor states and magnetism, whereas substituting Ge and Sn for In induces shallow donor impurity states in these monolayers. Furthermore, the results show that substituting Sn for In provides effective n-type carriers in the InSe monolayer because of the low formation energy and transition level (∼61.10 meV). These results should be helpful for related experimental studies.