We propose a novel technique that can compensate patterning effect by optimizing the modulation current of RSOAs, and successfully demonstrate 10.5-Gbit/s 8-PSK signal generation by directly-modulated RSOA having modulation bandwidth of only 0.9-GHz.
The crystallization and transformation behaviors from amorphous and crystalline silica to tridymite were investigated. Silica glass and precipitated silica as an amorphous silica and quartz as a crystalline silica were used for silica source. These silica were well mixed with tridymite as a seed crystal and fired at a temperature from 1100°C to 1400°C for 4, 6 and 12 h to form tridymite phase. The effect of CaO as a dopant on the formation of tridymite was also examined. Regardless to the presence or absence of CaO, the seed crystal tridymite was needed for phase transformation from amorphous silica or quartz to tridymite. In addition, it was found that silica glass was easier to transform to tridymite phase than precipitated silica and quartz. For samples without CaO, tridymite could be directly achieved from amorphous silica without the assistance of liquid phase. For samples doped with CaO, on the other hands, the dominant reaction for transformation to tridymite was the precipitation from liquid phase that was caused by the reaction between doped CaO and cristobalite crystallized from amorphous silica. The significant behaviors that occurred in the samples with CaO were (1) the formation of cristobalite and CaSiO3 which reduced tridymite amount and (2) the liquid phase formation which led the precipitation of tridymite.
We demonstrate a simple self-polarization-stabilization technique for the long-reach RSOA-based WDM PON implemented with self-homodyne receivers. The effectiveness of this technique is confirmed in 2.5-Gb/s transmission experiments over 68-km long link partially composed of installed fibers.
We demonstrate 10-Gb/s, 80-km-reach RSOA-based WDM PON by utilizing the digital coherent detection and electronic phase equalization techniques. The upstream signal is obtained by directly modulating a TO-can packaged RSOA with 10-Gb/s QPSK signal.
