title: Interplay between strong coupling and radiative damping of excitons and surface plasmon polaritons in hybrid nanostructures.
abstract: We report on the interplay between strong coupling and radiative damping of strongly coupled excitons (Xs) and surface plasmon polaritons (SPPs) in a hybrid system made of J-aggregates and metal nanostructures. The optical response of the system is probed at the field level by angle-resolved spectral interferometry. We show that two different energy transfer channels coexist: coherent resonant dipole-dipole interaction and an incoherent exchange due to the spontaneous emissions of a photon by one emitter and its subsequent reabsorption by another. The interplay between both pathways results in a pronounced modification of the radiative damping due to the formation of super- and subradiant polariton states. This is confirmed by probing the ultrafast nonlinear response of the polariton system and explained within a coupled oscillator model. Such a strong modification of the radiative damping opens up interesting directions in coherent active plasmonics.
authors.affiliation: Institut für Physik and Center of Interface Science, Carl von Ossietzky Universität Oldenburg , D-26111 Oldenburg, Germany.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Parinda
authors.initials: P
authors.lastname: Vasa
authors.forename: Robert
authors.initials: R
authors.lastname: Pomraenke
authors.forename: Ralf
authors.initials: R
authors.lastname: Vogelgesang
authors.forename: Antonietta
authors.initials: A
authors.lastname: De Sio
authors.forename: Ephraim
authors.initials: E
authors.lastname: Sommer
authors.forename: Margherita
authors.initials: M
authors.lastname: Maiuri
authors.forename: Cristian
authors.initials: C
authors.lastname: Manzoni
authors.forename: Giulio
authors.initials: G
authors.lastname: Cerullo
authors.forename: Christoph
authors.initials: C
authors.lastname: Lienau