Tamm-like states in finite antidot lattices - art. no. 035313

Transport properties of finite antidots arrays, with large lattice paramete rs and electron densities, may be roughly understood from a semiclassical a pproach. For weak magnetic fields, commensurability effects between the ant idot spacing and the cyclotron radius are present with interference pattern s superimposed on the magnetoresistivity. For higher magnetic fields, trans port through edge states becomes relevant. In the present work, we discuss a completely different behavior that should occur in the quantum limit, for short lattice parameters and small electron densities. The key feature is the formation of surface Tamm-like states within the gap of the lowest bulk bands of a finite antidot lattice. The surface of a finite antidot superla ttice may act as an isolated quantum ring, a coupler of the superlattice to the contacts, or a barrier between the bulk of the antidot lattice and the contacts, as a function solely of the applied magnetic field.