Electronic transmission through a polyacene ladder with a substitutional edge impurity

We provide an analytical and numerical study of the electronic and transport properties of a ladder system composed of two coupled chains, arranged in the ladder polymer and in the polyacene lattice topology, with a single substitutional edge impurity embedded in one of them. We evidence in particular the connection between local density of states, transmittivity, and occurrence of Fano resonances in the transmission spectra. Comparison of the local density of states and charge transmittivity through the two different ladder systems, as the impurity position is varied, contributes to evidence the nature of resonant interactions occurring for electronic energies coinciding with the impurity energy.