Magnetic proximity effects in van der Waals heterostructures provide an optical route to manipulate valley pseudospins in transition-metal dichalcogenides, but abrupt switching of two-dimensional (2D) ferromagnets (FM) limits continuous valley modulation. We demonstrate that the proximity-induced valley response of WSe 2 can be modified by engineering the interfacial magnetic environment in WSe 2 –CrBr 3 –CrPS 4 heterostructures. Circularly polarized magneto-photoluminescence reveals robust nonvolatile valley polarization in WSe 2 –CrBr 3 with a pronounced low-field hysteresis tracking CrBr 3 magnetization. Spectroscopy and calculations indicate that spin-selective interfacial charge transfer and orbital hybridization enhance the proximity exchange field and valley Zeeman splitting. Introducing antiferromagnetic (AFM) CrPS 4 weakens the degree of circular polarization modulation and broadens the low-field valley polarization reversal, consistent with an interfacial AFM/FM exchange pinning scenario. These results show that interfacial magnetic engineering can tailor proximity-induced valley responses in 2D heterostructures.
Li et al. (Sun,) studied this question.