Monolayer NbF: a 4d-analogue of cuprates.

The electronic structure and possible electronic orders in monolayer NbF are investigated by density functional theory and functional renormalization group. Because of the niobium-centered octahedra, the energy band near the Fermi level is found to derive from the 4d orbital, well separated from the other bands. Local Coulomb interaction drives the undoped system into an antiferromagnetic insulator. Upon suitable electron/hole doping, the system is found to develop [Formula: see text] -wave superconductivity with sizable transition temperature. Therefore, the monolayer NbF may be an exciting 4d analogue of cuprates, providing a new two-dimensional platform for high-T superconductivity.