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arXiv · 1501.04662

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

Wen-Yu Shan·Jianhui Zhou·Di Xiao
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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.

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Wen-Yu Shan, Jianhui Zhou, Di Xiao. 2015-01-19. Optical generation and detection of pure valley current in monolayer transition metal dichalcogenides. https://doi.org/10.1103/physrevb.91.035402

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