Generalized formulation for performance degradations due to bending and edge scattering loss in microdisk resonators.
We present a generalized formulation for the treatment of both bending (whispering gallery) loss and scattering loss due to edge roughness in microdisk resonators. The results are applicable to microrings and related geometries. For thin disks with radii greater than the bend-loss limit, we find that the finesse limited by the scattering losses induced by edge roughness is independent of radii. While a strong lateral refractive index contrast is necessary to prevent bending losses, unless the radii are of the order of a few microns, lateral air-cladding is detrimental and only enhances scattering losses. The generalized formulation provides a framework for selecting the refractive index contrast that optimizes the finesse at a given radius.
Heebner
John E
JE
Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, CA 94550, USA. heebner1@llnl.gov
Bond
Tiziana C
TC
Kallman
Jeff S
JS