Atomically thin MoS₂: a new direct-gap semiconductor.

@article{Mak2010AtomicallyTM,
  title={Atomically thin MoS₂: a new direct-gap semiconductor.},
  author={Kin Fai Mak and Changgu Lee and James C. Hone and Jie Shan and Tony F. Heinz},
  journal={Physical review letters},
  year={2010},
  volume={105 13},
  pages={
          136805
        }
}
The electronic properties of ultrathin crystals of molybdenum disulfide consisting of N=1,2,…,6 S-Mo-S monolayers have been investigated by optical spectroscopy. Through characterization by absorption, photoluminescence, and photoconductivity spectroscopy, we trace the effect of quantum confinement on the material's electronic structure. With decreasing thickness, the indirect band gap, which lies below the direct gap in the bulk material, shifts upwards in energy by more than 0.6 eV. This… 
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