Single-Layer Behavior and Its Breakdown in Twisted Graphene Layers

被引:561
作者
Luican, A. [1 ]
Li, Guohong [1 ]
Reina, A. [2 ]
Kong, J. [3 ]
Nair, R. R. [4 ]
Novoselov, K. S. [4 ]
Geim, A. K. [4 ,5 ]
Andrei, E. Y. [1 ]
机构
[1] Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08855 USA
[2] MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA
[3] MIT, Dept Elect Engn & Comp Sci, Cambridge, MA 02139 USA
[4] Univ Manchester, Sch Phys & Astron, Manchester M13 9PL, Lancs, England
[5] Univ Manchester, Manchester Ctr Mesosci & Nanotechnol, Manchester M13 9PL, Lancs, England
基金
英国工程与自然科学研究理事会; 美国国家科学基金会;
关键词
SCANNING-TUNNELING-MICROSCOPY; LARGE-AREA; GRAPHITE; FILMS;
D O I
10.1103/PhysRevLett.106.126802
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
We report high magnetic field scanning tunneling microscopy and Landau level spectroscopy of twisted graphene layers grown by chemical vapor deposition. For twist angles exceeding similar to 3 degrees the low energy carriers exhibit Landau level spectra characteristic of massless Dirac fermions. Above 20 degrees the layers effectively decouple and the electronic properties are indistinguishable from those in single-layer graphene, while for smaller angles we observe a slowdown of the carrier velocity which is strongly angle dependent. At the smallest angles the spectra are dominated by twist-induced van Hove singularities and the Dirac fermions eventually become localized. An unexpected electron-hole asymmetry is observed which is substantially larger than the asymmetry in either single or untwisted bilayer graphene.
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页数:4
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共 30 条
[1]   Properties of graphene: a theoretical perspective [J].
Abergel, D. S. L. ;
Apalkov, V. ;
Berashevich, J. ;
Ziegler, K. ;
Chakraborty, Tapash .
ADVANCES IN PHYSICS, 2010, 59 (04) :261-482
[2]  
BISTRITZER R, ARXIV10094203V1
[3]   The electronic properties of graphene [J].
Castro Neto, A. H. ;
Guinea, F. ;
Peres, N. M. R. ;
Novoselov, K. S. ;
Geim, A. K. .
REVIEWS OF MODERN PHYSICS, 2009, 81 (01) :109-162
[4]   Epitaxial graphene [J].
de Heer, Walt A. ;
Berger, Claire ;
Wu, Xiaosong ;
First, Phillip N. ;
Conrad, Edward H. ;
Li, Xuebin ;
Li, Tianbo ;
Sprinkle, Michael ;
Hass, Joanna ;
Sadowski, Marcin L. ;
Potemski, Marek ;
Martinez, Gerard .
SOLID STATE COMMUNICATIONS, 2007, 143 (1-2) :92-100
[5]   Localization of Dirac Electrons in Rotated Graphene Bilayers [J].
de laissardiere, G. Trambly ;
Mayou, D. ;
Magaud, L. .
NANO LETTERS, 2010, 10 (03) :804-808
[6]   Cyclotron resonance study of the electron and hole velocity in graphene monolayers [J].
Deacon, R. S. ;
Chuang, K.-C. ;
Nicholas, R. J. ;
Novoselov, K. S. ;
Geim, A. K. .
PHYSICAL REVIEW B, 2007, 76 (08)
[7]   Graphene bilayer with a twist: Electronic structure [J].
dos Santos, J. M. B. Lopes ;
Peres, N. M. R. ;
Castro Neto, A. H. .
PHYSICAL REVIEW LETTERS, 2007, 99 (25)
[8]   Electronic states and Landau levels in graphene stacks [J].
Guinea, F. ;
Castro Neto, A. H. ;
Peres, N. M. R. .
PHYSICAL REVIEW B, 2006, 73 (24)
[9]   Why multilayer graphene on 4H-SiC(000(1)over-bar) behaves like a single sheet of graphene [J].
Hass, J. ;
Varchon, F. ;
Millan-Otoya, J. E. ;
Sprinkle, M. ;
Sharma, N. ;
De Heer, W. A. ;
Berger, C. ;
First, P. N. ;
Magaud, L. ;
Conrad, E. H. .
PHYSICAL REVIEW LETTERS, 2008, 100 (12)
[10]   Large-scale pattern growth of graphene films for stretchable transparent electrodes [J].
Kim, Keun Soo ;
Zhao, Yue ;
Jang, Houk ;
Lee, Sang Yoon ;
Kim, Jong Min ;
Kim, Kwang S. ;
Ahn, Jong-Hyun ;
Kim, Philip ;
Choi, Jae-Young ;
Hong, Byung Hee .
NATURE, 2009, 457 (7230) :706-710