Laser-fabricated delay lines in GaAs for optically steered phased-array radar

We have used laser direct fabrication techniques to implement optical delay lines on an epitaxial GaAs/AlGaAs substrate. These integrated photonic circuits, which are important for optically-controlled phased-array radar, include asymmetric splitters with various splitting ratios, smoothly curved 90/spl deg/ bends, as well as linear waveguides. The delay lines were tested and found to have the desired delay and a power-output uniformity of /spl plusmn/2-4%.<
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