Nitrogen-doping induces tunable magnetism in ReS2

Abstract Transition metal dichalcogenides (TMDs) are promising for spintronic devices owing to their spin-orbit coupling and loss of inversion symmetry. However, further development was obstructed by their intrinsic nonmagnetic property. Doping TMDs with non-metal light atoms has been predicted to be a good option to induce unexpected magnetic properties which remain rarely explored. Here, we utilize nitrogen doping to introduce magnetic domains into anisotropic ReS₂, giving rise to a transition from nonmagnetic to tunable magnetic ordering. Both of the experimental and computational results confirmed that the N-doping in ReS₂ prefers to take place at the edge site than in-plane site. With controlled doping concentration, it exhibits a unique ferromagnetic-antiferromagnetic (FM-AFM) coupling. Assisted by theoretical calculations, we demonstrated that FM-AFM coupling presents a strong link to doping contents and doping sites. Wherein, the FM ordering mostly comes from N atoms and the AFM ordering originate from Re atoms. At the N-doping content of 4.24%, the saturated magnetization of N-doped ReS₂ reached the largest value of 2.1 emu g⁻¹ at 2 K. Further altering the content to 6.64%, the saturated magnetization of N-doped ReS₂ decreases, but exhibits a distinct exchange bias (EB) phenomenon of around 200 Oe. With controlled N-doping concentrations, the intrinsic spin in ReS₂ could be well altered and resulted in distinct magnetism, presenting tremendous potential for spintronic devices in information storage.