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.
@article{arxiv.1501.04662,
title = {Optical generation and detection of pure valley current in monolayer transition metal dichalcogenides},
author = {Wen-Yu Shan and Jianhui Zhou and Di Xiao},
journal= {arXiv preprint arXiv:1501.04662},
year = {2015}
}