Optical generation and detection of pure valley current in monolayer transition metal dichalcogenides

TL;DR

This paper presents a practical optical method to generate and detect pure valley currents in monolayer transition metal dichalcogenides, enabling ultrafast valley manipulation using linearly polarized light.

Contribution

It introduces a novel scheme for pure valley current generation via one-photon absorption and discusses detection methods, advancing valleytronics technology.

Findings

Pure valley current can be generated with linearly polarized light.

Detection is possible through photoluminescence or pump-probe techniques.

Tilted field influences valley current behavior.

Abstract

We propose a practical scheme to generate a pure valley current in monolayer transition metal dichalcogenides by one-photon absorption of linearly polarized light. We show that the pure valley current can be detected by either photoluminescence measurements or the ultrafast pump-probe technique. Our method, together with the previously demonstrated generation of valley polarization, opens up the exciting possibility of ultrafast optical-only manipulation of the valley index. The tilted field effect on the valley current in experiment is also discussed.