Modeling of Ring Resonator of Noninteger Indices

This paper reports the rigorous modeling of ring resonators that support resonant modes of non-integer indices found recently. A one-dimensional model satisfying the resonant condition of a ring resonator is derived and validated by comparing the results obtained by full-wave simulations. The modal profiles of a circular ring resonator under quadraturephase excitation illustrate the characteristics of progressive modal transitions from integer to non-integer indices.