60 GHz Optical Carrier Generation Using a Domain Reversed LiNbO₃ Optical Modulator

A 30 GHz bandpass modulator was fabricated on a domain reversed LiNbO3substrate. The circuit effect on current waveforms during wafer-scale poling was analyzed, and the domain wall movement was precisely controlled in the poling process. A complementary polarization reversal technique enabled the device with a single electrode structure to perform balanced modulation. A 60 GHz optical carrier was generated by double sideband modulation with the suppressed carrier. The fabricated device showed that carrier suppression was better than 45 dB and that the power ratio of a 60 GHz spaced two-tone lightwave signal to the suppressed carrier was 35 dB.