Propagation characteristics of optical solitons

When an optical pulse is transmitted in an optical fiber, the pulse will be broadened due to the dispersion effect, while the pulse will be compressed due to the nonlinear effect. When the two effects are balanced with each other, a peculiar phenomenon-optical soliton is produced. Optical soliton is a special wave packet that can be transmitted over long distances without distortion. Its uniqueness makes it have huge potential application value in the field of optical fiber communication, and provides a new solution for the optical communication system of ultra-long distance and ultra-large capacity transmission. At the same time, it is studying the dispersion effect and nonlinear effect in the optical fiber (cross-phase modulation XPM, self-phase modulation SPM, four-wave mixing (FWM), it is found that the dispersion and nonlinear characteristics of the fiber can be used to generate a supercontinuum. The transmission of optical pulses in optical fibers can be described by the general nonlinear Schrödinger equation, and then the split-step Fourier method can be used to simulate the transmission of optical pulses in optical fibers in MATLAB. Through simulation, we can see the stable transmission of the optical soliton, and at the same time changing the parameters according to different actual conditions, we can see the influence of dispersion and different nonlinear effects on the transmission of optical pulses.