Quantum-Hall activation gaps in graphene |
| |
Authors: | Giesbers A J M Zeitler U Katsnelson M I Ponomarenko L A Mohiuddin T M Maan J C |
| |
Institution: | High Field Magnet Laboratory, Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands. J.Giesbers@science.ru.nl |
| |
Abstract: | 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. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|