Angular-momentum coupling of optical whispering-gallery modes to liquid droplet microresonators

Starting from a recently developed model based on the generalized Lorenz-Mie theory, we simulate and experimentally investigate the resonance spectrum and the scattered light field of whispering-gallery modes (WGMs) in a liquid droplet excited with a free-space visible laser beam. Depending on the illumination configuration and the spectral region, we observe WGMs with diverse quality factors and coupling efficiencies. Through imaging of...