Research Of All-Optical Logic Gates Based On Nonlinear Effects Of Fiber

The Optical logic gate has a widespread application in the optical storage, opticalcalculation, optical switch and all optical networks. Responding speed is the one of the importantperformance parameters of logic gate. At present, the research both at home and abroad in thefield of realizing optical logic gate is mainly focused on using the performance of nonlinearcharacters of SOA. Since responding speed of this kind of optical logic gate based on SOA onlyreach the magnitude of Gbit/s limited by the gain recovery velocity of carrier. Highly nonlinearfiber possesses many unique advantages such as high speed, low power consumption, highefficiency, good nonlinear characteristics, and so on. The all optical logic gate based on thenonlinearities of optical fibers has the potential of operating at terabits per second, which make ita strong candidate to realize All optical logic devices.This paper presents the theoretical and experimental researches on all optical logicoperation on nonlinear effects of fiber. Several kinds of all optical logic gates are numericalanalyzed and simulated. The main contents are listed as follows:(1) The research background and signification of all optical logic gates is introduced. Theprimary technical solutions for all optical logic are reviewed. According to our experimentalconditions, all optical logic gates based on the nonlinear effects of fiber are considered to bestudied.(2) Starting from the nonlinear Schrodinger equation are discussed in the fiber self phasemodulation, cross phase modulation, optical pulse of several nonlinear effects in optical fibertransmission medium impact.(3) A scheme for all optical logic AND gate based on XPM effect of fiber is investigated.Using Matlab software programming, a 10 Gbit/s AND gate is realized by numerical simulation,some key factors which influence output performance are also studied. The 10Gbit / s all opticallogic AND gate simulation carried out by using Optisystem. There is a good agreement betweentheoretical and experimental results. Finally the paper proposes an improvement program based on self phase modulation (SPM) of fiber, performance of the system is optimized.(4) A scheme for all optical logic XOR gate based on XPM effect of fiber is investigated.Using Matlab software programming, a 10 Gbit/s XOR gate is realized by numerical simulation.The 10Gbit / s all optical logic XOR gate simulation carried out by using Optisystem., there is agood agreement between theoretical and experimental results. According to the simulate results,the paper proposes two improvement programs based on self phase modulation (SPM) of fiberand Kerr Shutter, bate the peaks and performance of the system is optimized. Finally a schemefor all optical logic OR gate based on XPM effect of fiber is investigated. A 10 Gbit/s all opticallogic OR gate signals has been simulated, and the simulation results are analyzed.