Optical nanoresonator in the ridge of photonic crystal waveguides crossing

A new geometry of nonlinear optical resonators in the ridge photonic crystal waveguides is suggested and numerically studied. The symmetry features of resonance modes are explored. It is established that the resonance mode has one axis of reflection symmetry axis for the cylindrical resonator and two axes of reflection symmetry for the ring resonator. It is demonstrated that the resonance mode with two axes of symmetry permits to construct an effective optical resonator. Two ways of optimization of the suggested resonators are explored. First, the optimization with the slit is considered. Second, the different infiltrated materials are investigated. The calculated resonators have the quality factor value about 104 and a small mode volume.