  We report the magneto-transport properties of a two-dimensional electron gas
in a modulation-doped AlGaAs/GaAs heterostructure subjected to a lateral
potential with honeycomb geometry. Periodic oscillations of the
magneto-resistance and a delocalized-localized transition are shown by applying
a gate voltage. We argue that electrons in such artificial-graphene lattices
offer a promising approach for the simulation of quantum phases dictated by
Coulomb interactions.
