Dynamic Fano Resonance in Thin Fiber Taper Coupled Cylindrical Microcavity

Abstract

Fano resonance results from interference between a background and a resonant scattering, which produces the asymmetrical lineshape. A cylindrical microcavity naturally possesses localized whispering gallery mode (WGM) and delocalized radiation mode, and a thin fiber taper can excite these two modes simultaneously. The localized WGM can interfere with the weak delocalized background to generate Fano resonance in the thin fiber taper coupled cylindrical microcavity. In addition, the Fano parameter can be adjusted by changing the gap between fiber taper and microcylinder cavity or the coupling diameter of fiber taper. The experimental results agree well with the quantum scattering theory.