ANALYSIS OF GAAS SCHOTTKY CONTACT TRAVELING-WAVE OPTICAL COUPLERS

Traveling wave directional coupler-type electro-optic modulators based on GaAs Schottky contact microstrip lines are modeled and analyzed. T he microwave propagation including losses in the structure is describe d by a simple quasi-TEM model. The lightwave propagation is calculated numerically including multiple layer effects as well as Schottky meta l cladding effects. A simple figure of merit is used to compare and op timize structures. The results show that the effects of microwave atte nuation dominate those of velocity and impedance mismatching at more t han 1 GHz and that the device performance is strongly dependent on the operating voltage.