Bound states in the continuum in a two-channel Fano-Anderson model

TL;DR

This paper investigates the formation of bound states in the continuum within a two-channel Fano-Anderson model, revealing conditions for true BICs and their potential applications in electronic and photonic systems.

Contribution

It introduces a Green's function and equation of motion approach to identify conditions for BICs in a symmetric two-channel model with degenerate impurity levels.

Findings

True BICs occur in symmetric configurations with degenerate impurity levels.

Complete transmission suppression is achieved at BICs.

Mechanism applicable to electronic and photonic systems.

Abstract

In this article, we study the formation of the bound states in the continuum (BICs) in a two-channel Fano-Anderson model. We employ the Green's function formalism, together with the equation of motion method, to analyze the relevant observables, such as the transmission coefficient and the density of states. Most importantly, our results show that the system hosts true BICs for the case of a symmetric configuration with the degenerate impurity levels, and a complete transmission channel is then suppressed. Finally, we argue that the proposed mechanism could be relevant for the realization of BICs in the electronic and photonic systems.