Quantum-hall activation gaps in graphene

被引：96

作者：

Giesbers, A. J. M. ^{[1
]}

Zeitler, U.

Katsnelson, M. I.

Ponomarenko, L. A.

Mohiuddin, T. M.

Maan, J. C.

机构：

[1] Radboud Univ Nijmegen, Inst Mol Mat, High Field Magnet Lab, Toernooiveld 7, NL-6525 ED Nijmegen, Netherlands

[2] Radboud Univ Nijmegen, Inst Mol Mat, Condensed Matter Theory, NL-6525 ED Nijmegen, Netherlands

[3] Univ Manchester, Dept Phys, Manchester M13 9PL, Lancs, England

来源：

PHYSICAL REVIEW LETTERS | 2007年 / 99卷 / 20期

关键词：

D O I：

10.1103/PhysRevLett.99.206803

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We have measured the quantum-Hall activation gaps in graphene at filling factors nu=2 and nu=6 for magnetic fields up to 32 T and temperatures from 4 to 300 K. The nu=6 gap can be described by thermal excitation to broadened Landau levels with a width of 400 K. In contrast, the gap measured at nu=2 is strongly temperature and field dependent and approaches the expected value for sharp Landau levels for fields B > 20 T and temperatures T > 100 K. We explain this surprising behavior by a narrowing of the lowest Landau level.

引用

页数：4

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