Directly visualizing the momentum-forbidden dark excitons and their dynamics in atomically thin semiconductors

  title={Directly visualizing the momentum-forbidden dark excitons and their dynamics in atomically thin semiconductors},
  author={Julien Mad{\'e}o and Michael K. L. Man and Chakradhar Sahoo and Marshall Campbell and Vivek Pareek and E. Laine Wong and Abdullah Al-Mahboob and Nicholas S. Chan and Arka Karmakar and Bala Murali Krishna Mariserla and Xiaoqin Li and Tony F. Heinz and Ting Cao and Keshav M. Dani},
  pages={1199 - 1204}
Probing the dark state Excitons, electron-hole pairs held together by Coulomb attraction, can be generated in semiconductors under excitation and greatly influence the material's optoelectronic properties. Although bright excitons are optically active, their dark-state cousins have been more difficult to detect. They do, however, affect the optoelectronic properties through their interaction with light and bright excitons. Madéo et al. developed a pump-probe photoemission technique that is used… Expand
A quantitative comparison of time-of-flight momentum microscopes and hemispherical analyzers for time-resolved ARPES experiments
Time-of-flight-based momentum microscopy has a growing presence in photoemission studies, as it enables parallel energy- and momentum-resolved acquisition of the full photoelectron distribution.Expand
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This work directly image the excitonic wave function in reciprocal space by measuring the momentum distribution of electrons photoemitting from excitons in monolayer tungsten diselenide and confirms the elusive theoretical prediction that the photoemitted electron exhibits an inverted energy-momentum dispersion relationship reflecting the valence band where the partner hole remains. Expand
Quantum beats of coherent 1s 2s excitons in two dimensional transition metal
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The exciton landscape in transition metal dichalcogenides is crucial for their optical properties and difficult to measure experimentally, since many exciton states are not accessible to opticalExpand
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Transition metal dichalcogenides have a rich exciton landscape consisting of a variety of bright and dark excitonic states. We consider the lowest-energy dark states in MoS2, which can be referred toExpand
Angle-resolved photoemission studies of quantum materials
  • J. Sobota, Yu He, Zhi-Xun Shen
  • Reviews of Modern Physics
  • 2021
Coherence and de-coherence in the Time-Resolved ARPES of realistic materials: an ab-initio perspective
Coherence and de–coherence are the most fundamental steps that follow the initial photo–excitation occurring in typical P&p experiments. Indeed, the initial external laser pulse transfers coherenceExpand
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We review recent progress in utilizing ultrafast light-matter interaction to control the macroscopic properties of quantum materials. Particular emphasis is placed on photoinduced phenomena that doExpand
Dark exciton-exciton annihilation in monolayer transition-metal dichalcogenides
Daniel Erkensten1,∗ , Samuel Brem, Koloman Wagner, Roland Gillen, Raül Perea-Cauśın, Jonas D. Ziegler, Takashi Taniguchi, Kenji Watanabe, Janina Maultzsch, Alexey Chernikov, and Ermin Malic 1Expand
Dark interlayer excitons in WS$_2$/tetracene heterostructures
Maja Feierabend, Victoria Lumsargis, Joshua J. P. Thompson, Kang Wang, Letian Dou, Libai Huang and Ermin Malic 1 Department of Physics, Chalmers University of Technology, 412 96 Gothenburg, Sweden 2Expand


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