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arXiv · 0904.4191

Engineering artificial graphene in a two-dimensional electron gas

M. Gibertini·A. Singha·V. Pellegrini·M. Polini·G. Vignale·A. Pinczuk·L. N. Pfeiffer·K. W. West
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Abstract

At low energy, electrons in doped graphene sheets behave like massless Dirac fermions with a Fermi velocity which does not depend on carrier density. Here we show that modulating a two-dimensional electron gas with a long-wavelength periodic potential with honeycomb symmetry can lead to the creation of isolated massless Dirac points with tunable Fermi velocity. We provide detailed theoretical estimates to realize such artificial graphene-like system and discuss an experimental realization in a modulation-doped GaAs quantum well. Ultra high-mobility electrons with linearly-dispersing bands might open new venues for the studies of Dirac-fermion physics in semiconductors.

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M. Gibertini, A. Singha, V. Pellegrini, M. Polini, G. Vignale, A. Pinczuk, L. N. Pfeiffer, K. W. West. 2009-04-27. Engineering artificial graphene in a two-dimensional electron gas. https://doi.org/10.1103/physrevb.79.241406

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