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≈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.
@article{arxiv.1302.2014,
title = {Quantized coexisting electrons and holes in graphene measured using temperature dependent magneto-transport},
author = {E. V. Kurganova and S. Wiedmann and A. J. M. Giesbers and R. V. Gorbachev and K. S. Novoselov and M. I. Katsnelson and T. Tudorovskiy and J. C. Maan and U. Zeitler},
journal= {arXiv preprint arXiv:1302.2014},
year = {2013}
}
Comments
5 pages, 5 figures, corrected typo in author's name