Transmission in a Fano-Anderson chain with a topological defect

TL;DR

This paper investigates how the topology of a side unit in a Fano-Anderson chain affects Fano-resonance-assisted transport, revealing potential for topological phase detection and transmission control.

Contribution

It demonstrates that the topological nature of the side unit influences transmission properties, introducing a novel method for detecting topological phases via Fano resonances.

Findings

Topology affects Fano resonance features.

Dual links enable control over transmission dips.

Transmission characteristics can indicate topological phases.

Abstract

The Fano-Anderson chain consists of a linear lattice with a discrete side-unit, and exhibits Fano-resonant scattering due to coupling between the discrete states of the side-unit with the tight-binding continuum. We study Fano-resonance-assisted transport for the case of a topologically non-trivial 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 yield additional control.