Spectral properties of aperiodic Vogel spirals

By using the dyadic Green's matrix spectral method, we demonstrate that aperiodic deterministic Vogel spirals made of electric dipoles support light localization in three dimensions, an effect that does not occur in traditional uniform random media. We discover a transition from an extended to a localized regime by evaluating the Thouless conductance and by performing a finite-size scaling. Vogel spirals are suitable photonic platforms to localize light thanks to their distinctive structural correlation properties that enable collective electromagnetic excitations with strong light-matter coupling. By decomposing the dyadic field propagator in its different components we show that light localization in Vogel arrays originates from collective electromagnetic coupling involving the contributions of multiple length scales. Our results unveil the importance of structural correlations in deterministic aperiodic photonic media for the design of localized states with strongly enhanced light-matter interactions. In addition, our findings may open new vistas for the engineering of mesoscopic transport and localization phenomena and should encourage deeper investigations of photonic devices based on deterministic aperiodic architectures.