Ultra-smooth microcylindrical resonators fabricated from the silicon optical fiber platform

Abstract

High quality hydrogenated amorphous silicon microcylindrical resonators are fabricated using the recently developed semiconductor optical fiber platform. The resonators are shown to have ultra-smooth surfaces that minimize the effects of scattering losses and exhibit localized whispering gallery modes with loaded quality factors of up to ∼2.8 × 104. Coupled mode theory indicates that the system quality factor is limited by both the bulk material loss of the resonator and the tapered fiber coupling scheme. The large extinction ratios and thermal nonlinearities measured in these microcylindrical resonators suggest that they should find application for low-power all-optical processing.