The Research Of All-optical Flip-flop Based On Semiconductor Optical Amplifier

In all-optical networks, semiconductor optical amplifiers (SOAs) are important devices for realizing all-optical signal processing and compensation loss due to its advantages of small size, high nonlinear coefficient, low power consumption and easy integration. In the field of all-optical signal processing, SOA plays an important role. All-optical logic gates and all-optical flip-flops are the basic techniques in all-optical signal processing field. Therefore, this scheme of the research of all-optical flip-flops based on semiconductor optical amplifier is of theoretical significance and academic value.In this paper, all-optical logic gates and all-optical flip-flops are studied. The main contents are as follows:(1) The theoretical analysis and simulation of all-optical logic gates based on SOA are studied.The principle of logic gate scheme based on nonlinear polarization rotation of SOA is introduced, and the classical model of SOA is simulated by programming software matlab. In the simulation, the bit rate is 1 Gb/s and 2.5 Gb/s, and the extinction ratio is about 30 dB. As the logic gate is a device that constitutes all-optical flip-flop, it is necessary to make the best of the logic gate simulation results to lay the foundation for the all-optical flip-flop simulation.(2) The theoretical analysis and simulation of all-optical flip-flop based on SOA Mach-Zehnder interferometer is studied.The principle of the all-optical flip-flop scheme based on the Mach-Zehnder Interferometer (MZI) is introduced. In this scheme, two Mach-Zehnder interferometer structures are coupled together by a polarization beam splitter. This structure takes advantage of the cross-phase modulation effect in SOA. All-optical logic gate and coupling Mach-Zehnder structure combine to form all-optical flip-flop. In this scheme, it simulated four types of all-optical flip-flops including D-, T-,SR- and JK- types of flip-flops.(3) The theoretical analysis and simulation of an all-optical flip-flops based on SOA polarization switch (PSW) are studied.The principle of all-optical flip-flop based on SOA polarization switch is introduced. In this scheme, the two polarization switches are coupled together by a polarization beam splitter, which utilizes the nonlinear polarization rotation effect in SOA. Combining the realization of the logic gate structure, we have carried out D-, T-, SR-, JK- types of four flip-flop. These four flip-flops have different logical structures. In the simulation, the first kind of situation adopts the bit rate of 1 Gb/s.However, in order to prove that this structure can achieve a higher bit rate in the simulation, for all-optical SR and JK flip-flop, we also used a bit rate of 2.5 Gb/s for the simulation study.