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Ultrafast Coulomb-Induced Intervalley Coupling in Atomically Thin WS2.

Robert Schmidt1, Gunnar Berghäuser2, Robert Schneider1

  • 1Institute of Physics and Center for Nanotechnology, University of Münster , 48149 Münster, Germany.

Nano Letters
|April 19, 2016
PubMed
Summary

Coulomb interactions in tungsten disulfide (WS2) monolayers drive ultrafast intervalley dynamics, explaining spectral signals and low polarization observed in experiments. This insight applies to other 2D semiconductors like MoS2 and WSe2.

Keywords:
2D materialsscreened Coulomb matrix elementstransition metal dichalcogenidesultrafast valley dynamics

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