60 GHz guided-wave electro-optic modulator using novel electrode structure of coupled microstrip line resonator

A guided-wave electro-optic modulator is proposed and its operation of optical intensity modulation by 60 GHz millimeter-wave signals is successfully confirmed. The modulator uses a newly developed electrode structure consisting of coupled microstrip lines. A high voltage can be induced by the resonance of the odd propagation mode to realize efficient electro-optic modulation even at millimeter-wave frequencies. The properties of the coupled microstrip lines were evaluated to show the effectiveness as a modulation electrode. The modulator designed at 60 GHz was fabricated with LiNbO/sub 3/ waveguides. The measured modulation coefficient normalized at 1 cm electrode length and 100 mW signal input was 2.4 rad.