Optical generation of excitonic valley coherence in monolayer WSe2.

@article{Jones2013OpticalGO,
  title={Optical generation of excitonic valley coherence in monolayer WSe2.},
  author={Aaron M Jones and Hongyi Yu and Nirmal J. Ghimire and Sanfeng Wu and Grant Aivazian and Jason S. Ross and Bo Zhao and Jiaqiang Yan and David G. Mandrus and Di Xiao and Wang Yao and Xiaodong Xu},
  journal={Nature nanotechnology},
  year={2013},
  volume={8 9},
  pages={
          634-8
        }
}
As a consequence of degeneracies arising from crystal symmetries, it is possible for electron states at band-edges ('valleys') to have additional spin-like quantum numbers. An important question is whether coherent manipulation can be performed on such valley pseudospins, analogous to that implemented using true spin, in the quest for quantum technologies. Here, we show that valley coherence can be generated and detected. Because excitons in a single valley emit circularly polarized photons… Expand
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