Slow-wave electrodes on GaAs for integrated electro-optic modulators

Abstract

Slow-wave electrodes that are suitable for use in integrated-optics, electro-optic modulators were fabricated and tested. Measurements of the microwave indices on a number of these electrodes show that sufficient slowing can be obtained to match the velocities of modulating microwaves to optical waves in graded-index AlxGa1−xAs waveguides for a wide range of mole fraction, x. Calculations based on the measured losses, for integrated-optics, electro-optic modulators in which the velocity-match condition has been achieved, indicate that devices having optical bandwidths >100 GHz should be possible using the electrodes presented.