Exchange Coupling-Induced Giant Spin Splitting in Two-Dimensional M2X3/TMD Heterostructures

Two-dimensional (2D) magnet–insulator heterostructures have shown potential as promising platforms for tuning valleytronics and spintronics. Thanks to their two-dimensional nature, possible candidates for realizing even richer quantum phases have been extended to a huge family of materials. Targeting the search for heterostructures with better performance, we suggest a Dirac electronic system M₂X₃ (M = transition metal, X = O/S) coupled with transition metal dichalcogenides (TMDs) as a new heterostructure family. We conduct a systematic first-principles study on electronic band properties and magnetic properties of M₂X₃/TMD heterostructures. On this ground, we reveal that there exists a giant spin splitting larger than the previously reported Cr-based system and identify the origin of this giant spin splitting as exchange coupling in this heterostructure. The efficient Zeeman field is up to 580 T in Cr₂O₃/WS₂. Our study suggests that M₂X₃/TMD can be a potential platform for realizing skyrmions. Due to its advantage as a simpler structure and a Dirac electronic system over the reported CrI₃ family in realization of such a spin system, M₂X₃/TMD holds the promise of discovering even richer quantum phases within the system.