Design and realization of an integrated optic switch for crossbarswitching arrays

An electrooptic switch that is insensitive to parameter tolerances is proposed for use in crossbar switching arrays. It makes use of intrinsically mismatched and tapered directional couplers and allows the realization of switching arrays with the same switching voltage for each element. Computations are carried out to verify a realization with Ti:LiNbO₃ waveguides and to compare the latter with conventional directional couplers. Switching elements on Z-cut LiNbO₃ with a crosstalk of -27 dB for zero voltage and a switching voltage of 27.5 V have been realized for use at 1.3 μm