Direct evidence for efficient ultrafast charge separation in epitaxial WS2/graphene heterostructures

@article{Aeschlimann2020DirectEF,
  title={Direct evidence for efficient ultrafast charge separation in epitaxial WS2/graphene heterostructures},
  author={Sven Aeschlimann and A Rossi and Mariana Ch{\'a}vez-Cervantes and Razvan Krause and Benito Arnoldi and Benjamin Stadtm{\"u}ller and Martin Aeschlimann and Stiven Forti and Filippo Fabbri and Camilla Coletti and Isabella Gierz},
  journal={Science Advances},
  year={2020},
  volume={6}
}
We reveal ultrafast charge separation in a WS2/graphene heterostructure possibly enabling optical spin injection into graphene. We use time- and angle-resolved photoemission spectroscopy (tr-ARPES) to investigate ultrafast charge transfer in an epitaxial heterostructure made of monolayer WS2 and graphene. This heterostructure combines the benefits of a direct-gap semiconductor with strong spin-orbit coupling and strong light-matter interaction with those of a semimetal hosting massless carriers… Expand
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