Transport in gapped bilayer graphene: The role of potential fluctuations

被引：88

作者：

Zou, K. ^{[1
]}

Zhu, J. ^{[1
]}

机构：

[1] Penn State Univ, Dept Phys, University Pk, PA 16802 USA

来源：

PHYSICAL REVIEW B | 2010年 / 82卷 / 08期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1103/PhysRevB.82.081407

中图分类号：

T [工业技术];

学科分类号：

08 ;

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.

引用

页数：4

共 25 条

[1] Biased bilayer graphene: Semiconductor with a gap tunable by the electric field effect [J].

Castro, Eduardo V. ;

Novoselov, K. S. ;

Morozov, S. V. ;

Peres, N. M. R. ;

Dos Santos, J. M. B. Lopes ;

Nilsson, Johan ;

Guinea, F. ;

Geim, A. K. ;

Castro Neto, A. H. .

PHYSICAL REVIEW LETTERS, 2007, 99 (21)

[2] Mapping the Dirac point in gated bilayer graphene [J].

Deshpande, A. ;

Bao, W. ;

Zhao, Z. ;

Lau, C. N. ;

LeRoy, B. J. .

APPLIED PHYSICS LETTERS, 2009, 95 (24)

[3] Broken-symmetry states and divergent resistance in suspended bilayer graphene [J].

Feldman, Benjamin E. ;

Martin, Jens ;

Yacoby, Amir .

NATURE PHYSICS, 2009, 5 (12) :889-893

[4] Ab initio study of gap opening and screening effects in gated bilayer graphene [J].

Gava, Paola ;

Lazzeri, Michele ;

Saitta, A. Marco ;

Mauri, Francesco .

PHYSICAL REVIEW B, 2009, 79 (16)

[5]

JING L, UNPUB

[6] Chiral tunnelling and the Klein paradox in graphene [J].

Katsnelson, M. I. ;

Novoselov, K. S. ;

Geim, A. K. .

NATURE PHYSICS, 2006, 2 (09) :620-625

[7]

KIM S, ARXIV09092288

[8] Infrared spectroscopy of electronic bands in bilayer graphene [J].

Kuzmenko, A. B. ;

van Heumen, E. ;

van der Marel, D. ;

Lerch, P. ;

Blake, P. ;

Novoselov, K. S. ;

Geim, A. K. .

PHYSICAL REVIEW B, 2009, 79 (11)

[9] Observation of an Electric-Field-Induced Band Gap in Bilayer Graphene by Infrared Spectroscopy [J].

Mak, Kin Fai ;

Lui, Chun Hung ;

Shan, Jie ;

Heinz, Tony F. .

PHYSICAL REVIEW LETTERS, 2009, 102 (25)

[10] Observation of electron-hole puddles in graphene using a scanning single-electron transistor [J].

Martin, J. ;

Akerman, N. ;

Ulbricht, G. ;

Lohmann, T. ;

Smet, J. H. ;

Von Klitzing, K. ;

Yacoby, A. .

NATURE PHYSICS, 2008, 4 (02) :144-148

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