| Nowadays,communication has brought convenience to people.The capacity and speed of information transmission in communication are the foundation of the Internet of everything.Compared with the traditional electronic communication system,the all-optical communication network is no longer affected by the"electronic bottleneck"because of its consumes less time and accurately information exchange.As a main device of all-optical communication network,all-optical logic gates have engrossed the attention of scholars at domestic and overseas.This paper uses the nonlinear effects of semiconductor optical amplifiers(SOA),Sagnac interferometers(SI),nonlinear dual-core fiber couplers and other optical devices to carry out theoretical research and simulation analysis on all-optical logic gates.Specific research contents and main achievements are listed below:(1)An all-optical logic gate system based on SOA-SI is designed.The pump signal is used as the control signal to analyze the influence of the pump power on the SOA carrier number and gain.When the two input pump signals have the same wavelength at 1555nm,the splitting ratio is 0.5,and the speed is 10Gb/s,the SOA-SI scheme is used to realize the exclusive OR gate or NOR gate.In the simulation experiment,the extinction ratios of the T port and R port were 14.47 d B and 5.12d B,the Q factor was 8.79 d B and 7.92 d B,and the bit error rate was as low as 1.82×10-14and 2.80×10-10.The good opening of the eye diagram shows that the output signals at the T and R ports have high logical accuracy and quality.(2)For the SOA-SI system,when the input wavelengths of the two pump signals are 1549 nm and 1556 nm,and the splitting ratio is 0.85,the new A2=(?)1 B2 logic operation and all-optical logic NOR gate are realized.In the simulation experiment,the extinction ratios of the T port and R port are 6.57 d B and 5.07 d B,the Q factor is 8.02 d B and 7.66 d B,and the bit error rate is as low as 1.15×10-10and 2.69×10-10,respectively.Through comparison,it is found that the evaluation coefficient of the NOR gate obtained when the input pump signal wavelength is different is compared with the NOR gate obtained when the input wavelength is the same,the extinction ratio is reduced by 0.5d B,the quality factor is reduced by 0.26 d B,and the bit error rate is higher than 0.11×10-10,so when the all-optical NOR gate is implemented,it is better to choose the same input wavelength.(3)Designed an all-optical logic gate system based on a nonlinear dual-core fiber coupler,and conducted theoretical analysis and experimental simulation on the system.In the simulation,the coupling coefficient k=50 m-1,the nonlinear coefficient ?=100 1/m.W,the coupling length L=?/2k=0.03m,the pump power1P range from 0 to 10W,and the probe light u0 is a continuous signal 1.00×10-3m W.Draw a graph of the transmission coefficient and the pump signal,and obtain a threshold power value of 0.40W,which changes the power of the pump signal at the two input ends for the critical point and analyzes the logical value of the output signal through the extinction ratio.The experimental results show that the all-optical logic gate system based on the nonlinear dual-core fiber coupler can realize the all-optical logic XOR gate and XOR gate. |
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