Giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor.

@article{Ugeda2014GiantBR,
  title={Giant bandgap renormalization and excitonic effects in a monolayer transition metal dichalcogenide semiconductor.},
  author={Miguel M. Ugeda and Aaron J. Bradley and Su-Fei Shi and Felipe H. da Jornada and Yu-Yang Zhang and Diana Yuan Qiu and Wei Ruan and S. K. Mo and Zahid Hussain and Zhi-Xun Shen and Feng Wang and Steven G. Louie and Michael F. Crommie},
  journal={Nature materials},
  year={2014},
  volume={13 12},
  pages={
          1091-5
        }
}
Two-dimensional (2D) transition metal dichalcogenides (TMDs) are emerging as a new platform for exploring 2D semiconductor physics. Reduced screening in two dimensions results in markedly enhanced electron-electron interactions, which have been predicted to generate giant bandgap renormalization and excitonic effects. Here we present a rigorous experimental observation of extraordinarily large exciton binding energy in a 2D semiconducting TMD. We determine the single-particle electronic bandgap… Expand
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