Topologically-protected states and their dynamical influence in structured reservoirs with chiral sublattice symmetry

We study the interaction of quantum emitters with a structured reservoir (background continuum) that acts as a topological insulator. Specifically, our structured reservoir is formed by a generalization of the Su-Scrieffer-Heeger (SSH) model that is extended to infinity, such that the continuous spectra includes two or more energy bands. In a previous work, we have shown that both localized and anti-localized zero-energy modes can form in the band gap of such systems and that these modes can absorb pairs of other eigenstates to form higher-order exceptional points (EPs) in some circumstances [1]. In the present work, we show that such states exist due to a chiral sublattice symmetry of the model and we examine their influence on quantum emitter state decay in a variety of circumstances.

[1] S. Garmon and K. Noba, Phys. Rev. A 104, 062215 (2021).