ANTIDOT-SUPERLATTICES - MINIBANDS AND MAGNETOTRANSPORT

Antidot-superlattices which are formed by imposing a periodic potential onto a two-dimensional electron gas of high mobility exhibit specific transport properties due to the competition between characteristic lengths: lattice constant, Fermi wavelength, mean free path, and magnetic length. The quantum mechanics of this system, which can be looked at as an artificial two-dimensional solid, is the content of this paper. The classical regime with larger lattice constants a and smaller antidot-radii R as realized in present experiments is compared with the quantum regime expected for smaller a and larger R. We analyze the energy band structure both without and with a perpendicular magnetic field and visualize the eigenstates by their probability density in view of classical periodic orbits. The latter have been shown recently by semiclassical transport calculations to be responsible for quantum oscillations seen in the experimental data. They can be detected also in the smoothed density of states obtained from the quantum eigenstates.