Charge and strain induced magnetism in monolayer MoS2 with S vacancy

The strain-induced magnetism in monolayer MoS2 with vacancy defects has caught great attention, but the effects of charged vacancies have been neglected by current works. Based on first principle calculations, we report on the electronic and magnetic properties of monolayer MoS2 with charged S vacancy and its strain effects. It is predicted monolayer MoS2 with charged S vacancy would undergo ferromagnetic-nonmagnetic-ferromagnetic phase transitions as strain increases from 0% to 6% and to 10%. The magnetism of monolayer MoS2 is related to two vacancy-induced defect states around the Fermi level. The ferromagnetic phase transition occurring in monolayer MoS2 can be attributed to charge transfer between the two defect states. We demonstrate how the ferromagnetic phase transition be controlled by gate electrode and tensile strain.