The optical waveguides containing phthalocyanine as an optically active material were fabricated and transmission properties were investigated experimentally and numerically. The positive refractive index change was observed in the glass waveguide with a vanadyl phthalocyanine thin film as a top layer. The thermal influence on refractive index change was estimated by surface plasmon measurements.

This paper proposes that a combination of pre-chirping and dispersion compensation is effective in suppressing the waveform distortion due to the self-phase modulation and the group-velocity dispersion in 10 Gb/s repeaterless transmission using 1.3-µm zero-dispersion single-mode fibers (SMF) operating at a wavelength of 1.55µm. The following results were obtained through simulation. 1) Setting the α-parameter of a LiNbO3 optical modulator negative (α1.0) gives a large tolerance of the launched power Pin. 2) For 90-km SMF transmission, the maximum Pin is obtained when the dispersion compensation ratio β is from 50% to 70%. 3) For the allowable β as a function of the transmission distance when a dispersion compensator is located in the receiver (post-compensation scheme), the lower limit of β is determined by the constant residual dispersion value, which agrees well with the dispersion tolerance without dispersion compensation. Our 90-km SMF transmission experiments using a LiNbO3 optical modulator and a dispersion compensating fiber (DCF) confirmed the simulation results regarding the optimum value of β and the large tolerance of the fiber launched power. Based on the above investigations, we achieved a 10-Gb/s repeaterless 140-km SMF transmission with α1.0 and post-compensation.