Quantum oscillations of valley current driven by microwave irradiation in transition-metal dichalcogenide/ferromagnet hybrids

TL;DR

This paper theoretically demonstrates that microwave-driven spin pumping in TMDC/ferromagnet heterostructures induces a valley-selective spin excitation, resulting in a pure valley current with quantum oscillations as a function of chemical potential, linking spintronics and valleytronics.

Contribution

It reveals how microwave irradiation can generate and control valley currents via quantum oscillations in TMDC/ferromagnet heterostructures, a novel pathway for valleytronics.

Findings

Valley-selective spin excitation induced by microwave-driven spin pumping.

Observation of quantum oscillations of valley current with chemical potential.

Identification of a signature of quantized valley states.

Abstract

We theoretically study spin and valley transport in a transition-metal dichalcogenide(TMDC)/ferromagnet heterostructure under a perpendicular magnetic field. We find that microwave-driven spin pumping induces a valley-selective spin excitation, a direct consequence of the valley-asymmetric Landau levels in the TMDC conduction band. This process generates a pure valley current which, as our central finding, exhibits pronounced quantum oscillations as a function of chemical potential. These oscillations provide a definitive experimental signature of the quantized valley states and establish another pathway to interface spintronics and valleytronics.