• 文献标题:   Transport in gapped bilayer graphene: The role of potential fluctuations
  • 文献类型:   Article
  • 作  者:   ZOU K, ZHU J
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   2469-9950 EI 2469-9969
  • 通讯作者地址:   Penn State Univ
  • 被引频次:   74
  • DOI:   10.1103/PhysRevB.82.081407
  • 出版年:   2010

▎ 摘  要

We employ a dual-gated geometry to control the band gap Delta in bilayer graphene and study the temperature dependence of the resistance at the charge neutrality point, R-NP(T), from 220 to 1.5 K. Above 5 K, R-NP(T) is dominated by two thermally activated processes in different temperature regimes and exhibits exp(T-3/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 Delta/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.