Recent advances in the engineering of light confinement have demonstrated the ability to fully control the spectral properties of an individual photonic mode in two-dimensional disordered photonic structures, paving the way for the creation of open transmission channels in strongly scattering media. The optical confinement and the coupling between modes open new perspectives over the control of the light flow in random media, as well as the possibility to build architectures tuned for efficient light-matter interaction.
We study a novel geometry, suspended Si3N4 membranes in which the disorder is introduced by shifting the holes by a small normally distributed displacement, to achieve coupling between single quantum emitters (Dibenzoterrylene (DBT) molecules, embedded in a thin anthracene crystals), and disordered photonic structures. In this way, adding disorder on top of an initial ordered structure, we tune the appearance of Anderson localized modes at the proper frequency, for coupling with DBT molecules. Our aim is to study the quasi-modes formation of a disordered pattern to create a chain of hybridized localized modes, extended from one end of the sample to the other. Such topology has the advantage of bringing distant molecules to exchange energy, thanks to the shared photonic mode.
Necklace states arise from the coupling of otherwise confined modes in disordered photonic systems and open high transmission channels in strongly scattering media. Despite their potential relevance in the transport properties of photonic systems, necklace state statistical occurrence in dimensions higher than one is hard to measure, because of the lack of a decisive signature. In this work we provide an efficient method to tell apart in a single measurement a coupled mode from a single localized state in a complex scattering problem, exploiting the analogy with well-characterized coupled cavities in photonic crystals. We study the phase spatial distribution of the electromagnetic field as a function of the coupling strength and of detuning between interacting modes respectively for coupled photonic crystal cavities and for partially disordered systems. Results consistently show that when localized modes spectrally and spatially overlap only over a small surface extent, synchronous oscillation does not build up and the phase spatial distribution splits into two distinct peaks .
-  Fabrizio Sgrignuoli, Giacomo Mazzamuto, Niccolò Caselli, Francesca Intonti, Francesco Saverio Cataliotti, Massimo Gurioli and Costanza Toninelli. Necklace state hallmark in disordered 2D photonic systems, ACS Photonics, 2015, 2 (11), pp 1636–1643.