Traveling-wave integrated optical modulator with a working-frequency bandwidth of 4 GHz

An investigation was made of a traveling-wave integrated optical modulator utilizing a microstrip electrode structure and tunnel-coupled channel waveguides formed in Ti:LiNbO₃. The modulator characteristics were as follows: the half-wave voltage was 10 V (at a wavelength of 1.3 μm), the working frequency bandwidth was at least 4 GHz, the dynamic range (for a laser radiation power of 5 mW) was about 40 dB, and the level of the higher harmonics (at 1 GHz) was 35 dB.