As the title implies the story is all about Artificial Graphene. Artificial graphene is a recently realized man-made nanosystem that exhibits graphene-like physics in a tunable setup. The system can be created by, e.g., positioning molecules in a triangular lattice on a metal surface. For the paper, we model finite flakes of artificial graphene on a real-space grid and calculate their single-electron properties as a function of the flake size and the strength of an external magnetic field. Our calculations reveal the gradual formation of Dirac cones as well as a self-similar Hofstadter butterfly as the flake size is increased. Moreover, the density of states agrees well with the experimental data with and without the magnetic field. In essence, we are able to determine the stability of Dirac points in finite flakes of artificial grapheme.
What's up next? Electronic and transport properties of Graphene are sensitive to the presence of atoms adsorbed on its surface. An important question, however, is whether the distribution of adatoms is always genuinely random. There are hints, that that dilute adatoms on graphene may have a tendency towards a spatially correlated state with a hidden Kekulé mosaic order.
Flake potential with Kekulé mosaic ordering. |
I will keep you updated on this very interesting project.