Spin Manipulation by Giant Valley-Zeeman Spin-Orbit Field in Atom-Thick WSe2

TL;DR

This paper demonstrates room-temperature spin flipping in monolayer WSe2 driven by a giant valley-Zeeman spin-orbit field, revealing a new method for efficient spin control in ultralow-power spintronic devices.

Contribution

It introduces the valley-Zeeman spin-orbit field as a novel mechanism for spin manipulation in atom-thick WSe2, with tunability via layer number, stacking, and gate voltage.

Findings

Spin flipping achieved at room temperature in WSe2.

Giant valley-Zeeman SOF estimated at 650 T.

Spin dynamics tunable by layer, stacking, and voltage.

Abstract

The phenomenon originating from spin-orbit coupling (SOC) provides energy-efficient strategies for spin manipulation and device applications. The broken inversion symmetry interface and resulting electric field induce a Rashba-type spin-orbit field (SOF), which has been demonstrated to generate spin-orbit torque for data storage applications. In this study, we found that spin flipping can be achieved by the valley-Zeeman SOF in monolayer WSe2 at room temperature, which manifests as a negative magnetoresistance in the vertical spin valve. Quantum transmission calculations based on an effective model near the K valley of WSe2 confirm the precessional spin transport of carriers under the giant SOF, which is estimated to be 650 T. In particular, the valley-Zeeman SOF-induced spin dynamics was demonstrated to be tunable with the layer number and stacking phase of WSe2 as well as the gate voltage, which provides a novel strategy for spin manipulation and can benefit the development of ultralow-power spintronic devices.