Study of mode locked fiber lasers and all-optical logic

Mode locked fiber laser and all-optical logic technologies are building blocks for the construction of all-optical networks in the information era. This Ph.D dissertation investigates essential mechanism related to the mode locked lasers and all-optical logic such as the multiwavelength laser source, multiwavelength pulses, high-speed short pulse generation, clock recovery and all optical Boolean functions. ^ First, a CW multiwavelength laser source oscillating in 75 wavelengths is proposed based on the semiconductor optical amplifier (SOA) enclosed in the fiber ring cavity, and the stability of the laser source will be investigated in detail. ^ In the optical time division multiplexing (OTDM) system, it\u27s of vital importance to generate optical pulses with narrow pulsewidth, high repetition rate, and long-term stability, towards this goal, an 80GHz short pulse train generation system is presented. ^ A high speed clock recovery operation is also demonstrated based on the Mach-Zehnder (MZ) modulator; the conversion efficiency of the proposed clock recovery circuit is analyzed numerically. ^ In addition, effective all-optical logic functions are also proposed to overcome a critical speed limit, Boolean OR, NOR, and AND functions are reported at the speed up to 80Gb/s using SOA based devices. These are the highest reported operating speed, at which the proposed all optical logic gates have been characterized.