The magnetic proximity effect (MPE) has recently been explored to manipulate interfacial properties of two-dimensional (2D) transition metal dichalcogenide (TMD)/ferromagnet heterostructures for use in spintronics and valleytronics. However, a full understanding of the MPE and its temperature and magnetic field evolution in these systems is lacking. In this study, the MPE has been probed in Pt/WS₂/BPIO (biphase iron oxide, Fe₃O₄ and α-Fe₂O₃) heterostructures through a comprehensive investigation of their magnetic and transport properties using magnetometry, four-probe resistivity, and anomalous Hall effect (AHE) measurements. Density functional theory (DFT) calculations are performed to complement the experimental findings. We found that the presence of monolayer WS₂ flakes reduces the magnetization of BPIO and hence the total magnetization of Pt/WS₂/BPIO at T > ~120 K—the Verwey transition temperature of Fe₃O₄ (T_V). However, an enhanced magnetization is achieved at T < T_V. In the latter case, a comparative analysis of the transport properties of Pt/WS₂/BPIO and Pt/BPIO from AHE measurements reveals ferromagnetic coupling at the WS₂/BPIO interface. Our study forms the foundation for understanding MPE-mediated interfacial properties and paves a new pathway for designing 2D TMD/magnet heterostructures for applications in spintronics, opto-spincaloritronics, and valleytronics.

Heterostructures composed of graphene and transition metal dichalcogenide layers can support ferromagnetism at room temperature that can be controlled by defect and doping engineering.