Push−pull thin−film optical modulator

An electro−optic amplitude modulator was made by placing two channel−defined waveguide phase modulators in the legs of a Jamin interferometer. Using a novel detection method, modulation was observed up to 1.8 GHz, although the roll−off in the modulator response started at about 750 MHz. Full amplitude modulation was produced by 17 V, giving a power band width characteristic for the separate phase modulators of 200 μW/MHz for a modulation index of 1 rad.