Spatial Coherence Properties of Organic Molecules Coupled to Plasmonic Surface Lattice Resonances in the Weak and Strong Coupling Regimes

Abstract

We study spatial coherence properties of a system composed of periodic silver nanoparticle arrays covered with a fluorescent organic molecule (DiD) film. The evolution of spatial coherence of this composite structure from the weak to the strong coupling regime is investigated by systematically varying the coupling strength between the localized DiD excitons and the collective, delocalized modes of the nanoparticle array known as surface lattice resonances. A gradual evolution of coherence from the weak to the strong coupling regime is observed, with the strong coupling features clearly visible in interference fringes. A high degree of spatial coherence is demonstrated in the strong coupling regime, even when the mode is very excitonlike (80 %), in contrast to the purely localized nature of molecular excitons. We show that coherence appears in proportion to the weight of the plasmonic component of the mode throughout the weak-to-strong coupling crossover, providing evidence for the hybrid nature of the normal modes.

Condensation phenomena in plasmonics

“…On top of the metallic array structure, we assume a number of quantum emitters that have a two-level structure where the levels are split into multiple sublevels; in practice the emitters can be dye molecules embedded in a polymer matrix, for example, with the electronic levels split into a rovibrationallevel substructure. Under appropriate conditions, plasmonic modes can strongly couple to molecules [19][20][21]; here, we consider only the weak-coupling regime. Therefore, we do not consider the possibility of condensation of light-matter hybrids in analogy to semiconductor exciton-polariton condensates [9,10] but phenomena more similar to the concept of photon condensation [12,22,23].…”

“…We take the absorption properties of the dye molecules to be those of DiD molecules (as used in our experiments in [21]). Importantly (based on the manufacturer's data) the emission profile is well predicted by the Kennard-Stepanov relation, proportional to B(ω)e −β( ω− ) at room temperature (β = 1/k B T ).…”

Ground‐State Chemical Reactivity under Vibrational Coupling to the Vacuum Electromagnetic Field

“…The coupling of molecular electronic transitions to the vacuum field has been more extensively studied13, 14, 15, 16, 17, 18 than VSC and has already shown many exciting results, such as enhanced conductivity19 and non‐radiative energy transfer,20 lasing,21 and condensation 22. Together with VSC, it clearly opens many new possibilities for molecular and materials science that should be fully explored.…”

Cavity-Enhanced Transport of Charge

“…PACS numbers: 05.60. Gg, 42.50.Pq, 74.40.Gh, The study of strong light-matter interactions [1][2][3][4] is playing an increasingly crucial role in understanding as well as engineering new states of matter with relevance to the fields of quantum optics [5][6][7][8][9][10][11][12][13][14][15][16][17][18], solid state physics [19][20][21][22][23][24][25][26][27][28][29][30][31], as well as quantum chemistry [32][33][34][35][36] and material science [37][38][39][40][41][42][43][44][45][46][47][48][49][...…”