| Because the ultrashort pulse laser has the advantages of extremely high peak power and extremely short pulse duration,it has been widely used in many cutting-edge fields such as physical chemistry,biological science,and material science.At the same time,with the development of science and technology and the deepening of applications,people’s requirements for ultrashort pulse lasers are more complicated.In more and more applications,multiple ultrashort pulses lasers or even multiple ultrashort pulses lasers from different bands are required to work synchronously.The ultrashort pulse light source system has evolved from a simple single device to a systematic,complex and collaborative system to realize more functions.Realizing the collaborative work of pulsed light sources has been paid more and more attention.Traditional multi-wavelength lasers and cross-band ultrashort pulse lasers have disadvantages such as environmental sensitivity,low synchronization accuracy and complex structure.A new method is provided in this paper to solve these problems.By changing the operation mode of traditional multi-wavelength lasers,the intrinsic synchronization of multi-wavelength lasers is realized by the all-optical regenerator using single cavity cascaded wavelength switching.And the supercontinuum in tapered fiber is used to realize multi-band synchronous pulse laser.The main research contents of the thesis are as follows:(1)The supercontinuum generated in the tapered single-mode fiber is analyzed.Using the mathematical model of femtosecond optical pulse evolution in tapered fiber,the supercontinuum generated by femtosecond optical pulse in tapered single-mode fiber is numerically simulated,and the three-band tapered fiber under different dispersion conditions is studied and analyzed.Generated supercontinuum.The tapered single-mode fiber used in the wavelength conversion between the three wavebands of 1μm to 1.5μm,1.5μm to 2μm,2μm to 1.5μm,and 1.5μm to 1μm has been successfully designed.(2)The traditional multi-wavelength laser with parallel working mode is changed to the cascade working mode in a single cavity,and Mamyshev regenerators are placed in one ring cavity to realize a 6-wavelength synchronous laser in the 2μm band for the first time.The power transfer function is used to optimizing the laser structure,and various parameters that affect the characteristics of the laser system are analyzed.(3)Combining the supercontinuum generated in the tapered single-mode fiber with the Mamyshev regenerator,for the first time,a single-ring cavity structured cross-threeband synchronous laser is realized through simulation.The synchronous output of femtosecond pulses of 1μm,1.5μm and 2μm is successfully realized in the single-ring cavity structure.The evolution process of the optical pulse in the laser is analyzed,and the influence of the system parameters on the laser is discussed. |
