Coherence and Density Dynamics of Excitons in a Single-Layer MoS2 Reaching the Homogeneous Limit

@article{Jakubczyk2019CoherenceAD,
  title={Coherence and Density Dynamics of Excitons in a Single-Layer MoS2 Reaching the Homogeneous Limit},
  author={Tomasz Jakubczyk and Goutham Nayak and Lorenzo Scarpelli and Wei-Lai Liu and Sudipta Dubey and Nedjma Bendiab and La{\"e}titia Marty and Takashi Taniguchi and Kenji Watanabe and Francesco Masia and Gilles Nogues and Johann Coraux and Wolfgang Werner Langbein and Julien Renard and Vincent Bouchiat and Jacek Kasprzak},
  journal={ACS Nano},
  year={2019},
  volume={13},
  pages={3500 - 3511}
}
We measure the coherent nonlinear response of excitons in a single layer of molybdenum disulfide embedded in hexagonal boron nitride, forming a h-BN/MoS2/h-BN heterostructure. Using four-wave mixing microscopy and imaging, we correlate the exciton inhomogeneous broadening with the homogeneous one and population lifetime. We find that the exciton dynamics is governed by microscopic disorder on top of the ideal crystal properties. Analyzing the exciton ultrafast density dynamics using amplitude… Expand
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