Basic module for an integrated optical phase difference measurement and correction system

A basic module for an integrated optical phase difference measurement and correction system was developed and fabricated in the AlGaAs-GaAs material system. The relative phase difference between two waveguides is measured using waveguide couplers to sample the optical field in each waveguide, a Y-junction interferometer with a small sinusoidal phase dither applied to one arm and a vertically integrated metal-semiconductor-metal detector. P/sup +/-n/sup -/n/sup +/ phase modulators are used to control the phase difference between the waveguides. This implementation makes it possible to measure and correct the relative phase difference between adjacent waveguides using only a few percent of the optical power of each guide.<
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