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arXiv · 2505.09524

Resonant cavity-QED with chiral flat bands

E. M. Broni·A. M. C. Souza·M. L. Lyra·F. A. B. F. de Moura·G. M. A. Almeida
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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.

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BibTeXRIS

E. M. Broni, A. M. C. Souza, M. L. Lyra, F. A. B. F. de Moura, G. M. A. Almeida. 2025-05-14. Resonant cavity-QED with chiral flat bands. https://doi.org/10.1103/t3n9-c8m9

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