Strain-Controllable Phase and Magnetism Transitions in Re-Doped MoTe₂ Monolayer

Developing approaches to effectively manipulate the magnetic states and phase transition is critical to the application of transition metal dichalcogenides (TMDs) in spintronic or phase-switching devices. In this work, Re doping and strain engineering are combined to control the phase transition between 2H-and 1T′-MoTe₂ and to induce magnetism in the system based on density functional theory calculations. The structural transformation from 2H-to 1T′-phase is predicted to occur around a doping concentration of 11%. The intrinsically nonmagnetic 2H-MoTe₂ structures with various doping concentrations become magnetic under a biaxial tensile strain, and the magnetic moment slowly increases with strain. For 1T′-MoTe₂, only monolayers with a doping concentration of less than 10% exhibit magnetism under relatively high strain. The conversion from ionic to covalent bonding and the self-exchange mechanisms are found to be the origin of the tunable magnetic behaviors under strain. The synchronous emergence of the structural transition and magnetism in Re-doped MoTe₂ under isotropic strain offers a great possibility to design novel and tunable spintronic devices.