The effect of bilayer regions on the response of epitaxial graphene devices to environmental gating. / Pearce, Ruth ; Eless, Viktoria; Lartsev, Arseniy; Barker Snook, I.L.; Helmore, J.J.; Yakimova, Rositza ; Gallop, J.C.; Hao, Ling.

In: Carbon, Vol. 93, 11.2015, p. 896-902.

Research output: Contribution to journalArticle

Published
  • Ruth Pearce
  • Viktoria Eless
  • Arseniy Lartsev
  • I.L. Barker Snook
  • J.J. Helmore
  • Rositza Yakimova
  • J.C. Gallop
  • Ling Hao

Abstract

The effect of a bilayer area on the electronic response to environmental gating of a monolayer graphene Hall bar device is investigated using room temperature magnetotransport and scanning Kelvin probe microscopy measurements in a controlled environment. The device is tuned through the charge neutrality point with n–p–n-junctions formed. Scanning Kelvin probe measurements show that the work function of the monolayer graphene decreases more than that of the bilayer area however magnetotransport measurements show a larger change in carrier concentration for bilayer graphene with environmental gating. Interface scattering at the boundary between the monolayer and bilayer regions also affects device response with field-dependent suppression of the conductivity observed near the charge neutrality point. Simultaneous electronic and environmental scanning Kelvin probe measurements are used to build nano-scale maps of the work function of the device surface revealing the areas of greatest work function change with environmental gating.
Original languageEnglish
Pages (from-to)896-902
Number of pages7
JournalCarbon
Volume93
Early online date23 May 2015
DOIs
Publication statusPublished - Nov 2015
This open access research output is licenced under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

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