Design and simulation of ring resonator optical switches using electro-optic materials

Ring resonator optical switches using electro-optic materials have been proposed. The propagation loss of the waveguides and the resonance characteristics of ring resonators with different refractive indices are simulated. The operation voltage is estimated based on the results of the simulations and is found to be 0.70 V in the case of the ring resonator switch with a K(Ta, Nb)O₃ core and KH₂PO₄ cladding layers. The time-dependent resonance characteristics are calculated by a simple model. The operation speed is limited by the resonance time and is less than 15 ps. This is different from optical switches with a Si core, where their operation speed is limited by not the resonance time but the free carrier accumulation time of the order of 102 ps. Ring resonator switches with electro-optic materials are promising devices for application to optically interconnected LSIs because of their size of around 20 μm and high operation frequency of more than 66 GHz.