Lateral leakage in TM-like whispering gallery mode of thin-ridge silicon-on-insulator disk resonators

The leakage loss due to TM-TE mode coupling of TM-like whispering gallery mode in silicon-on-insulator (SOI) thin-ridge disk resonators is investigated for the first time to the best of our knowledge. We show that the propagation losses of TM-like mode in thin-ridge SOI disk resonators are significantly impacted by the radius of the disk. This behaviour is predicted by a simple phenomenological model as well as a rigorous mode matching simulation.