Magnetic properties of two nearest Cu-doped monolayer WS2: A first-principles study

We investigate magnetic properties of Cu-doped monolayer WS2 for 6.25%, 8% and 12.5% Cu concentration using the first-principles methods based on density functional theory. The results show that one Cu-doped monolayer WS2 is non-magnetic, while two Cu-doped systems of the nearest neighbor configuration are ferromagnetic (FM). The hybridization between the Cu dopant and its neighboring S atoms results in the splitting of the energy levels near the Fermi energy. These results suggest the p-d hybridization mechanism for the magnetism of the Cu-doped WS2 monolayer structures. While the magnetic moment disappears with the increasing Cu-Cu distances. Our studies predict the nearest two Cu-doped WS2 monolayers to be candidates for thin dilute magnetic semiconductors. Moreover, the formation energy calculations also indicate that it is energy favorably and relatively easier to incorporate Cu atom into the WS2 monolayer under S-rich experimental conditions.