Resonant cavity-QED with chiral flat bands

TL;DR

This paper explores the interaction between a two-level emitter and chiral flat bands in photonic lattices, revealing robust light-matter coupling and potential for controlled quantum states.

Contribution

It demonstrates how flat band states can be prepared through quench dynamics and remain robust against structural disorder in cavity-QED systems.

Findings

Weak hopping disorder causes delocalization of the mode.

Emitter-field coupling strength remains protected against structural fluctuations.

Flat band states can be prepared via quench dynamics.

Abstract

Flat bands exhibit high degeneracy and intrinsic localization, offering a promising platform for enhanced light-matter interactions. Here, we investigate the resonant interaction between a two-level emitter and a chiral flat band hosted by a photonic lattice. In the weak coupling regime, the emitter undergoes Rabi oscillations with a lifted photonic mode whose spatial structure reflects the nature of compact localized states and the onset of Anderson localization. We show that weak hopping disorder induces a delocalization of the lifted mode whereas the effective emitter-field coupling strength, and the associated mode volume experienced by the emitter, remains protected against structural fluctuations. We illustrate our approach using selected flat band lattices. Our findings provide a route to flat band state preparation via quench dynamics and robust cavity-QED control.