Probing excitonic dark states in single-layer tungsten disulphide

@article{Ye2014ProbingED,
  title={Probing excitonic dark states in single-layer tungsten disulphide},
  author={Ziliang Ye and Ting Cao and Kevin J. O'Brien and Hanyu Zhu and Xiaobo Yin and Yuan Wang and Steven G. Louie and Xiang Zhang},
  journal={Nature},
  year={2014},
  volume={513},
  pages={214-218}
}
Transition metal dichalcogenide (TMDC) monolayers have recently emerged as an important class of two-dimensional semiconductors with potential for electronic and optoelectronic devices. Unlike semi-metallic graphene, layered TMDCs have a sizeable bandgap. More interestingly, when thinned down to a monolayer, TMDCs transform from indirect-bandgap to direct-bandgap semiconductors, exhibiting a number of intriguing optical phenomena such as valley-selective circular dichroism, doping-dependent… Expand
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