Answers are grounded in this paper and cite their sources.
We show that manipulation by a spatial profile of the refractive index of a circularly symmetric dielectric cavity results in a novel way of fine tuning frequency separations as well as spatial localizations of high-Q whispering-gallery modes excited in the cavity. The method permits dispersion compensation in the modes (spectrum equalization), diminishes the quality-factor limitation by surface roughness and contamination, and allows critical coupling to ultra-high-Q modes without maintaining an air gap with evanescent couplers.
No takes yet. Share an insight, caveat, or question.
Ilchenko et al. (2003) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: