Introduction
This note introduces how to derive the expression of optical power enhancement factor for a ring resonator, which is coupled to a bus waveguide to form the all-pass ring configuration [1]. The detailed derivation is available via this link.
Reference
[1] Bogaerts, W., De Heyn, P., Van Vaerenbergh, T., De Vos, K., Kumar Selvaraja, S., Claes, T., … & Baets, R. (2012). Silicon microring resonators. Laser & photonics reviews, 6(1), 47-73.