80GHz broadband electro-optical modulator with optical fiber structure

In this letter, a novel broadband optical fiber type M-Z modulator with traveling-wave electrode is proposed. Since the waveauides are formed using special optical fiber, the microwave field is concentrated in the optical fiber regions. The finite element method has been used to analyze the microwave equivalent refractive index and characteristic impedance. Then, the performance of the modulator has been simulated using the neural network. The calculated and simulation results are shown in figures. Compared with the conventional modulator, the novel modulator can easily obtain the velocity matching and impedance matching. Using this structure, we have developed a fiber type M-Z modulator with 80GHz; 3dB bandwidth, 1.18V half-wave driving voltage, and 55.5 Omega impedance.