Based On The Research Of High Nonlinear Optical Pulse Compression Technology

Ultrashort optical pulses have a wide range of applications in optical communications, optical signal processing, sensing technology, biomedical testing and other fields. Fiber-based pulse compression technology is one of the effective ways for getting ultrashort optical pulse. However the ordinary fiber has been restricted by its own parameters and can not get a good pulse compression effect. Highly nonlinear fiber (HNLF) can effectively overcome the deficiency of the ordinary fiber, and greatly improve the efficiency of pulse compression. Thus, the fiber-based pulse compression technology using HNLF has become a hotspot in the research of pulse compression technologies.In this thesis, the common pulse compression methods were introduced and their advantages and disadvantages were compared.Then the basic theory of pulse compression was expounded using the transmission characteristics of ultrashort optical pulses in the fiber. The methods based on the effect of soliton pulse compression were introduced and the experiment system of the soliton pulse compression using HNLF was designed. In the experiment system, a fiber laser based on SESAM and a passively mode-locked fiber laser based on nonlinear polarization rotation effect were used as inputs. In the experiment we observed significant pulse compression and obtained the shortest pulse width for135femtosecond. We analyzed the relation between the output pulse width and the input power. Using split-step Fourier method, we simulated the pulse compression based on the effect of soliton pulse compression, and compared the results of the simulation and the experiment.Finally, the pulse compression methods based on the comb-like profiled fiber (CPF) was introduced and the basic theory of the pulse compression in CPF was expounded. With the principle of the optical fiber design, we designed a CPF using high nonlinear fibers and standard single-mode fibers. Then we established a mathematical model of pulse compression in the CPF. From the simulation results we discussed varation of the compressed pulse width and the quality with the input power.