Transport in gapped bilayer graphene: The role of potential fluctuations

K. Zou, Jun Zhu

Research output: Contribution to journalArticle

77 Citations (Scopus)

Abstract

We employ a dual-gated geometry to control the band gap Δ in bilayer graphene and study the temperature dependence of the resistance at the charge neutrality point, RNP (T), from 220 to 1.5 K. Above 5 K, RNP (T) is dominated by two thermally activated processes in different temperature regimes and exhibits exp ( T3 /T ) 1/3 below 5 K. We develop a simple model to account for the experimental observations, which highlights the crucial role of localized states produced by potential fluctuations. The high-temperature conduction is attributed to thermal activation to the mobility edge. The activation energy approaches Δ/2 at large band gap. At intermediate and low temperatures, the dominant conduction mechanisms are nearest-neighbor hopping and variable-range hopping through localized states. Our systematic study provides a coherent understanding of transport in gapped bilayer graphene.

Original languageEnglish (US)
Article number081407
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume82
Issue number8
DOIs
StatePublished - Aug 17 2010

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Graphene
graphene
conduction
Energy gap
activation
activation energy
Temperature
temperature dependence
temperature
geometry
Activation energy
Chemical activation
Geometry

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

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Transport in gapped bilayer graphene : The role of potential fluctuations. / Zou, K.; Zhu, Jun.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 82, No. 8, 081407, 17.08.2010.

Research output: Contribution to journalArticle

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