L. A. Ponomarenko, R. V. Gorbachev, D. C. Elias, G. L. Yu, A. S. Mayorov, J. Wallbank, M. Mucha-Kruczynski, A. Patel, B. A. Piot, M. Potemski, I. V. Grigorieva, K. S. Novoselov, F. Guinea, V. I. Fal'ko, A. K. Geim
Lateral superlattices have attracted major interest with an ultimate goal of creating materials with designer electronic properties. However, it proved difficult to realize superlattices with sufficiently short periodicity and weak scattering, and most of the observed features could be explained in terms of commensurable semiclassical trajectories. We study transport properties of graphene aligned along crystallographic directions of encapsulating boron nitride and report a strong reconstruction of graphene's spectrum due to the moire potential. Second-generation Dirac points are observed as sharp peaks in resistivity with reversals of the Hall effect. Quantizing magnetic fields lead to secondary sets of Landau levels, Hofstadter-type cloning of further neutrality points and emerging fractal quantum Hall states.
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http://arxiv.org/abs/1212.5012
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