Transmission in a Fano-Anderson chain with a topological defect

Abstract

The Fano-Anderson chain consists of a linear lattice with a discrete side-unit, and it exhibits Fano-resonant scattering due to coupling between the discrete states of the side-unit and the tight-binding continuum. We study Fano-resonance-assisted transport for the case of a topologically nontrivial side unit. We find that the topology of the side-unit influences the transmission characteristics, which thus can be an effective detection tool of the topological phases of the side unit. Furthermore, we explore the role of dual links between the linear tight-binding chain and the side unit. The secondary connection between the main chain and the side-unit can modify the position or width of the Fano resonance dip in the transmission probability, and thus can yield additional control.