Ion-Induced Surface Charge Dynamics in Freestanding Monolayers of Graphene and MoS2 Probed by the Emission of Electrons

Anna Niggas (Corresponding author), Janine Schwestka, Karsten Balzer (Corresponding author), David Weichselbaum, Niclas Schlünzen, René Heller, Sascha Creutzburg, Heena Inani, Mukesh Tripathi, Carsten Speckmann, Niall McEvoy, Toma Susi, Jani Kotakoski, Ziyang Gan, Antony George, Andrey Turchanin, Michael Bonitz, Friedrich Aumayr, Richard A. Wilhelm (Corresponding author)

Publications: Contribution to journalArticlePeer Reviewed

Abstract

We compare the ion-induced electron emission from freestanding monolayers of graphene and MoS2 to find a sixfold higher number of emitted electrons for graphene even though both materials have similar work functions. An effective single-band Hubbard model explains this finding by a charge-up in MoS2 that prevents low energy electrons from escaping the surface within a period of a few femtoseconds after ion impact. We support these results by measuring the electron energy distribution for correlated pairs of electrons and transmitted ions. The majority of emitted primary electrons have an energy below 10 eV and are therefore subject to the dynamic charge-up effects at surfaces.

Original languageEnglish
Article number086802
Number of pages9
JournalPhysical Review Letters
Volume129
Issue number8
DOIs
Publication statusPublished - 19 Aug 2022

Austrian Fields of Science 2012

  • 103018 Materials physics
  • 103042 Electron microscopy

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