Quantum interference effects in particle transport through finite honeycomb clusters
Abstract
We study how quantum hopping transport in finite honeycomb clusters is influenced by quantum interference. The incident particle is governed by the quantum percolation Hamiltonian and thus traverses the cluster through nearest-neighbor hops. The conductance is then determined from the transmission coefficient of the particle's wavefunction. Since this is a single-particle model, quantum interference is the dominant factor in the transmission. We find transmission resonances and anti-resonances as the incident particle's energy is varied. These singularities appear to occur in regular intervals in energy. Some of the anti-resonances occur at particle energies corresponding to bound state energies of the cluster. A forbidden zone in the transmission also exists for a wide range of the particle's energy. Looking at the density of the particle's wavefunction, for highly transmitting configurations destructive interference is minimized while for highly reflecting configurations destructive interference is dominant.
