Mapping Unoccupied Electronic States of Freestanding Graphene by Angle-Resolved Low-Energy Electron Transmission

Abstract

We report angle-resolved electron transmission measurements through freestanding graphene sheets in the energy range of 18 to 30 eV above the Fermi level. The measurements are carried out in a low-energy electron point source microscope, which allows simultaneously probing the transmission for a large angular range. The characteristics of low-energy electron transmission through graphene depend on its electronic structure above the vacuum level. The experimental technique described here allows mapping the unoccupied band structure of freestanding two-dimensional materials as a function of energy and probing angle, respectively in-plane momentum. Our experimental findings are consistent with theoretical predictions of a resonance in the band structure of graphene above the vacuum level [V. U. Nazarov, E. E. Krasovskii, and V. M. Silkin, Physical Review B 87, 041405 (2013)].

References in corpus (3)

• Electric Field Effect in Atomically Thin Carbon Films
• Low-energy electron transmission imaging of clusters on free-standing graphene
• Scattering resonances in graphene

Cited by in corpus (7)

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• Negative transit time in non-tunneling electron transmission through graphene multilayers
• Phase retrieval methods applied to coherent imaging
• How to image single isolated atoms by using coherent low-energy electrons
• Symmetry of electron bands in graphene: (nearly) free electron vs. tight-binding