Effects of ridge depth on characteristics of shielded velocity-matched (SVM) Ti:LiNbO/sub 3/ optical modulators with ridge structures

The effects of ridge depth on the microwave effective index, characteristic impedance of the traveling-wave electrode, and modulation bandwidth of shielded velocity-matched Ti:LiNbO/sub 3/ optical modulators with ridges are investigated numerically. It is clarified that the driving voltage has an optimum ridge depth (3-4 mu m) for various gaps of the electrode, and there are optimum overlaid layer thicknesses at the velocity matching point for given values of the ridge depth.<
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