Vectorial Fluorescence Emission from Microsphere Coupled to Gold Mirror

We report on the generation, and momentum space distribution of fluorescence emission from individual SiO2 microsphere on dye coated Au mirror. The molecular fluorescence emission mediated via whispering gallery modes of the sphere is studied using polarization resolved optical energy-momentum micro-spectroscopy. Our experiments 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 micro-cavities 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.