Proximity-Driven Non-Volatile Spin and Valley Control in a Van Der Waals Antiferromagnetic Heterostructure.

Hu, Lili; Dong, Shan; Zhai, Yuxin; Wang, Yubin; Samanta, Debabrata; Tang, Yuhan; Sedmidubský, David; Sofer, Zdenek et al. · Adv Mater · 2026

basic_science · Level V

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Abstract

The integration of non-volatile spin and valley control in 2D quantum systems remains a pivotal challenge for spintronic and valleytronic functionalities. Here, we demonstrate persistent spin and valley polarizations in a van der Waals heterostructure comprising bulk antiferromagnetic CrPS<sub>4</sub> and monolayer MoSe<sub>2</sub>, achieved via interfacial magnetic proximity effects. The 1L-MoSe<sub>2</sub>/bulk-CrPS<sub>4</sub> heterostructure exhibits non-volatile hysteresis in chiral photoluminescence (PL), directly linked to the antiferromagnetic ordering of bulk-CrPS<sub>4</sub>. This helicity of PL persists at zero field, enabled by the spin-polarized charge transfer from the K valley in the MoSe<sub>2</sub> monolayer to the conduction band of CrPS<sub>4</sub>, breaking the valley degeneracy without external stimuli. Remarkably, the PL helicity switches surprisingly at a magnetic field of ∼ 0.5 T, a 17-fold smaller than the spin-flip field of ∼8.5 T in bulk CrPS<sub>4</sub>. Our work establishes bulk antiferromagnet-based heterostructure as a robust platform for low-energy, magnetically tunable quantum devices, bridging the gap between the transient valleytronic phenomena and practical non-volatile applications.