Electron dynamics of the buffer layer and bilayer graphene on SiC

Alex J. Shearer, James E. Johns, Benjamin W. Caplins, David E. Suich, Mark C Hersam, Charles B. Harris

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Angle- and time-resolved two-photon photoemission (TPPE) was used to investigate electronic states in the buffer layer of 4H-SiC(0001). An image potential state (IPS) series was observed on this strongly surface-bound buffer layer, and dispersion measurements indicated free-electron-like behavior for all states in this series. These results were compared with TPPE taken on bilayer graphene, which also show the existence of a free-electron-like IPS series. Lifetimes for the n = 2, and n = 3 states were obtained from time-resolved TPPE; slightly increased lifetimes were observed in the bilayer graphene sample for the n = 2 the n = 3 states. Despite the large band gap of graphene at the center of the Brillouin zone, the lifetime results demonstrate that the graphene layers do not behave as a simple tunneling barrier, suggesting that the buffer layer and graphene overlayers play a direct role in the decay of IPS electrons.

Original languageEnglish
Article number231604
JournalApplied Physics Letters
Volume104
Issue number23
DOIs
Publication statusPublished - Jun 9 2014

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graphene
buffers
photoelectric emission
electrons
life (durability)
free electrons
photons
electron states
Brillouin zones
decay
electronics

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Shearer, A. J., Johns, J. E., Caplins, B. W., Suich, D. E., Hersam, M. C., & Harris, C. B. (2014). Electron dynamics of the buffer layer and bilayer graphene on SiC. Applied Physics Letters, 104(23), [231604]. https://doi.org/10.1063/1.4882236

Electron dynamics of the buffer layer and bilayer graphene on SiC. / Shearer, Alex J.; Johns, James E.; Caplins, Benjamin W.; Suich, David E.; Hersam, Mark C; Harris, Charles B.

In: Applied Physics Letters, Vol. 104, No. 23, 231604, 09.06.2014.

Research output: Contribution to journalArticle

Shearer, AJ, Johns, JE, Caplins, BW, Suich, DE, Hersam, MC & Harris, CB 2014, 'Electron dynamics of the buffer layer and bilayer graphene on SiC', Applied Physics Letters, vol. 104, no. 23, 231604. https://doi.org/10.1063/1.4882236
Shearer, Alex J. ; Johns, James E. ; Caplins, Benjamin W. ; Suich, David E. ; Hersam, Mark C ; Harris, Charles B. / Electron dynamics of the buffer layer and bilayer graphene on SiC. In: Applied Physics Letters. 2014 ; Vol. 104, No. 23.
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