All-Optical Logic Operation Based On SOAs

All-optical logic gates, as the key component of all-optical networks and the base of photonic computers, have received much attention in recent years. Semiconductor optical amplifier (SOA) is a first candidate to realize all-optical logic gates due to its low power consume, small size and low response time. Theoretical and experimental researches on all-optical logic gates based on SOAs and filters are presented in this thesis, supported by the National High Technology Developing Program of China (Grant No. 2006AA03Z0414),the Science Fund for Distinguished Young Scholars of Hubei Province (Grant No. 2006ABB017) and the Program for New Century Excellent Talents in Ministry of Education of China (Grant No. NCET-04-0715).The main contents are listed as follows:(1) The research background and achievements of all-optical logic gates based on SOAs are clarified. The development direction of the research is discussed. The idea of utlizating variety nonlinear effect based on SOAs to achieve multifunctional logic gates is proposed.(2) SOA models for cross gain modulation (XGM), transient cross phase modulation (T-XPM) and four wave mixing (FWM) are introduced respectively. And the function of wavelength conversion utlizating these SOA model is simulated.(3) All-optical logic gates based on transient cross phase modulation are researched. A full set of logic gates based on two parallel SOAs is proposed. The principle of operation is investigated.. Multifuctional logic gates for three input signals are proposed and simulated. A novel AND gate based on a single SOA utlizating transient cross phase modulation is proposed and simulated. And some key factors to output performance are discussed.(4) Multifunctional logic gates based on XGM, T-XPM and FWM based on a single SOA is proposed. Experiment results for multifunctional logic gates(NOR, OR , AND, XNOR and NOT gate) of 10Gb/s NRZ format, 20Gb/s NRZ format, 20Gb/s RZ format, 40Gb/s NRZ format and 40Gb/s RZ format are obtained.(5) Multifunctional logic devices based on parallel SOAs are proposed. The principle of operation and theoretical model are presented. Theoretical results for multifunctional logic devices are discussed. Experimental results for all-optical encoder at 20Gb/s for both RZ and NRZ formats and all-optical digital encoder and comparator at 40Gb/s are presented.