Electro-optic and thermo-optic polymer micro-ring resonators and their applications

This thesis presents some novel devices using electro-optic polymers. The electro-optic polymer is used in a micro-ring resonator. First the micro-resonator characteristics are analyzed. The bending loss is calculated using computer program for polymer material to obtain the minimum-bending radius. An analytical formula is obtained for scattering loss from the rough sidewalls. The scattering loss is calculated for practical polymer devices. The coupling to the resonator is calculated using beam propagation method. The optimization of coupling is discussed. Some passive polymer micro-resonators are fabricated. The novel fabrication method is described. Filters with a finesse of 141 and free spectral range of 5nm at 1300 nm and finesse of 117 with a free spectral range of 8nm at 1550nm are demonstrated. The filters can be temperature tuned at the rate of 14GHz/°C. The control of resonance wavelength by changing the size of the micro-resonator is demonstrated. Resonant ring modulators, which use an electro-optic polymer, are demonstrated. For one set of devices with relatively large diameter the resonance wavelength voltage tunes at the rate of 0.82GHz/V. The modulators have a bandwidth larger than 2 GHz. Polymer micro-ring modulators with FSR larger than 1Thz, modulation bandwidth of 15GHz and the full with half maximum voltage of 20V are demonstrated at 1300nm by using Teflon AF cladding. The theory of mode coupling using electro-optic micro-resonators is presented. It is shown that these devices can be used as a wavelength converter or a comb generator. Widely tunable double micro-ring filters by thermo-optic effect and electro-optic effect are demonstrated. The tuning range is more than 40nm. 16V is required for 1nm tuning using electro-optic polymers. A widely tunable laser using this filter and EDFA gain is demonstrated. The side mode suppression ratio is greater than 30dB and the tuning range is 40nm.