Transport in graphene antidot barriers and tunneling devices

Periodic arrays of antidots, i.e., nanoscale perforations, in graphene enable tight confinement of carriers and efficient transport barriers. Such barriers evade the Klein tunneling mechanism by being of the mass rather than electrostatic type. While all graphene antidot lattices (GALs) may support directional barriers, we show, however, that a full transport gap exists only for certain orientations of the GAL. Moreover, we assess the applicability of gapped graphene and the Dirac continuum approach as simplified models of various antidot structures showing that, in particular, the former is an excellent approximation for transport in GALs supporting a bulk band gap. Finally, the transport properties of a GAL based resonant tunneling diode are analyzed indicating that such advanced graphene based devices may, indeed, be realized using GAL structures. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4768844]