Phase tuning by laser ablation of LiNbO/sub 3/ interferometric modulators to optimum linearity

Fast, accurate phase bias trimming of LiNbO/sub 3/ interferometric modulators by excimer laser ablation is reported. Phase angle measurements and correction were performed in situ on a previously fabricated, packaged modulator. Any angle can be precisely adjusted to 90 degrees (maximum linearity). Single-laser-pulse exposures on one interferometer arm caused changes in angle of 0.8-8 degrees , depending on laser fluence and the depth of the material removed.<
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