The Study Of Self-similar Pulse In Fiber Amplifier

With the development of science and technology and the enhancement of humandemand for communication, optical fiber communication is closely connected with people’slife. Many people are interested in the characteristics of light pulse self-similar properties,Physics and other subjects are prompted rapidly by the self-similarity, such as quantum fieldtheory, fluid dynamics, plasma physics, condensed matter physics and biophysics, etc. Andthese areas are based on the characteristics of the self-similar pulse. Firstly, the fiberparameters and the pulse initial energy determines the self-similar characteristic of pulsetransmission, and the self-similar characteristics has nothing to do with the input pulseshape, and we can get all the energy of a pulse from the output of the pulse; Secondly,owingto the existence of self-similarity, the pulse has a good ability of resistance to divide, andcan keep the waveform stability, even in the case of high power, the pulse shape will noteasily change; Thirdly, pulses chirps strict linear played an important role in the pulsecompression with high efficiency, with high power and no base do limit approximationtransform femtosecond light pulse, and lay a theoretical and practical foundation.Mainly, this paper are based on the nonlinear Schr dinger equation, and firstly, thesolutions of the non-locality and nonlinear Schr dinger equation are explored, and theparabolic solutions and the initial chirps are confirmed by the method of numericalsimulation in non-locality and nonlinear Schr dinger equation, and the existence conditionsof dark solitons and bright solitons are discussed.Then on the basis of the nonlinearSchr dinger equation, GLE with constant coefficients of evolution are obtained. and we canknow that gain dispersion can adjust the shape of pulse is analyzed by comparing with theNLSE. In the case of very small gain dispersion, the pulse transmission in comb-likedispersion optical fiber DDF and CDPF are analyzed, including the influence of gaindispersion, pulse width and the initial energy of pulse transmission. Moreover, the pulsetransmission in this two kinds of optical fiber of are studied compressed further. Finally,based on the GLE equation, we study the pair of pulses transmission, including pulseamplitude, pulse width and phase, input pulse, etc, at the same time,we also probes into the pair of pulse in the comb-like dispersion optical fiber, the results show that pulsetransmission in Raman fiber amplifier is not affected by adjacent pulses, just sinusoidaloscillation occurs in the overlap region due to the pulse of the linear superposition, afterseparating, the pulses keep their transmission characteristics respectively.