Quantized coexisting electrons and holes in graphene measured using temperature dependent magneto-transport

Autor: Kurganova, E. V., Wiedmann, S., Giesbers, A. J. M., Gorbachev, R. V., Novoselov, K. S., Katsnelson, M. I., Tudorovskiy, T., Maan, J. C., Zeitler, U.
Rok vydání: 2013
Předmět:
Zdroj: Phys. Rev. B 87, 085447 (2013)
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevB.87.085447
Popis: We present temperature-dependent magneto-transport experiments around the charge neutrality point in graphene and determine the amplitude of potential fluctuations $s$ responsible for the formation of electron-hole puddles. The experimental value $s \approx 20$ meV is considerably larger than in conventional semiconductors which implies a strong localization of charge carriers observable up to room temperature. Surprisingly, in the quantized regime, the Hall resistivity overshoots the highest plateau values at high temperatures. We demonstrate by model calculations that such a peculiar behavior is expected in any system with coexisting electrons and holes when the energy spectrum is quantized and the carriers are partially localized.
Comment: 5 pages, 5 figures, corrected typo in author's name
Databáze: arXiv