Vectorial Fluorescence Emission from Microsphere Coupled to Gold Mirror

The generation and momentum space distribution of fluorescence emission from individual SiO2 microsphere on dye-coated Au mirror are reported here. The molecular fluorescence emission mediated via whispering gallery modes of the sphere is studied using polarization-resolved optical energy-momentum microspectroscopy. The experiments of this study reveal intensity dependence of split modes of the cavity as a function of in-plane wavevector and emission polarization in the far field. The exotic far-field distribution can be understood by sphere-image sphere model that further reveals the polarization dependence of the split modes. The presented results reveal the potential of metallo-dielectric soft microcavities to engineer molecular emission that can encode spin and orbital angular momentum states and can be further extrapolated to realize dye-loaded active meta-atoms and meta-surfaces.