Experimental measurement of the intrinsic excitonic wave function

@article{Man2020ExperimentalMO,
  title={Experimental measurement of the intrinsic excitonic wave function},
  author={Michael K. L. Man and Julien Mad{\'e}o and Chakradhar Sahoo and Kaichen Xie and Marshall Campbell and Vivek Pareek and Arka Karmakar and E. Laine Wong and Abdullah Al‐Mahboob and Nicholas S. Chan and David R Bacon and Xing Zhu and Mohamed Abdelrasoul and Xiaoqin Li and Tony F. Heinz and Felipe H. da Jornada and Ting Cao and Keshav M. Dani},
  journal={Science Advances},
  year={2020},
  volume={7}
}
We visualize the distribution of the electron around the hole in an exciton and observe its elusive anomalous dispersion. An exciton, a two-body composite quasiparticle formed of an electron and hole, is a fundamental optical excitation in condensed matter systems. Since its discovery nearly a century ago, a measurement of the excitonic wave function has remained beyond experimental reach. Here, we directly image the excitonic wave function in reciprocal space by measuring the momentum… 

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