Bandpass traveling-wave Mach-Zehnder modulator in LiNbO3 with domain reversal

A bandpass traveling-wave Mach-Zehnder modulator is demonstrated in a Z-cut LiNbO₃ substrate where quasi-phase-matching is achieved by using a crystal domain reversal and a simple uniform coplanar waveguide electrode structure. The domain reversal was created, by using electric-field poling, to implement the three-section alternating electrooptic interaction. At the operating wavelength /spl lambda/=1.32 μm, the modulator has a 15 GHz-broad bandpass response centered at 25-GHz 3.6-dB fiber-to-fiber insertion loss, 12 V on-off voltage at the center frequency, and -33-dB extinction ratio.