Spectrally Programmable Spin-Polarized Photocurrents in WSe$_2$-NiPS$_3$ Magnetic van der Waals Heterostructures

Rajesh Kumar Yadav; Michal Poplinger; Adi Levi; Adi Harchol; Nirman Chakraborty; Thomas Brumme; Thomas Heine; Efrat Lifshitz; Doron Naveh

arXiv · 2608.23832

Spectrally Programmable Spin-Polarized Photocurrents in WSe$_2$-NiPS$_3$ Magnetic van der Waals Heterostructures

Rajesh Kumar Yadav·Michal Poplinger·Adi Levi·Adi Harchol·Nirman Chakraborty·Thomas Brumme·Thomas Heine·Efrat Lifshitz·Doron Naveh

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Abstract

Efficient generation and control of spin-polarized currents in semiconductors remain central challenges for spin-based electronics, particularly due to impedance mismatch and the reliance on magnetic fields or ferromagnetic contacts. Here, we introduce a materials platform for spectrally programmable spin transport based on a van der Waals heterostructure combining the antiferromagnetic semiconductor NiPS$_3$ with WSe$_2$. In a p-n diode architecture, circularly polarized excitation produces pronounced photoconductive resonances with spin polarization reaching 80% near the Neel temperature and persisting at 30% at room temperature. Remarkably, selected spectral bands retain their polarization sign across the magnetic phase transition, evidencing robust, spectrally protected spin-polarized current generation. Polarization-resolved photogalvanic measurements reveal a dominant circular injection-current mechanism, confirming spin-polarized carrier transport. First-principles calculations show that an applied electric field induces interfacial hybridization and spin-layer locking, giving rise to localized symmetry breaking and enhanced optical absorption while preserving global time-reversal symmetry. These results establish spectral tuning of excitation as a new control knob for spin transport, enabling spin-current generation without magnetic fields or polarization switching. Our findings position magnetic van der Waals heterostructures as a versatile platform for opto-spintronic functionality and spectrally programmable spintronic devices.

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Rajesh Kumar Yadav, Michal Poplinger, Adi Levi, Adi Harchol, Nirman Chakraborty, Thomas Brumme, Thomas Heine, Efrat Lifshitz, Doron Naveh. 2026-08-24. Spectrally Programmable Spin-Polarized Photocurrents in WSe$_2$-NiPS$_3$ Magnetic van der Waals Heterostructures. https://arxiv.org/abs/2608.23832

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