We report on experiments where high-Q silicon nitride microdisks couple to arrays of plasmon antennas. Such hybrids promise `best of both world’ performances, i.e., subwavelength mode volume yet high Q, with exciting repercussions for spontaneous emission control, sensing, and plasmon-enhanced Raman scattering. In this framework it is particularly interesting to understand antenna-antenna interactions mediated through a resonant cavity. In a first experiment we examine cooperative dipole-dipole coupling of antenna dimers coupled through a whispering gallery mode, and demonstrate implications for high-Purcell factors with `chiral’, properties, i.e., unidirectional circulation. In a second experiment we studied far-field OAM generation by rings of antennas on cavities, demonstrating simultaneous pure OAM and pure polarization control through unit-cell design. Finally we report on the potential of such structures for molecular optomechanics.
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