Study Of Chirped Pulse Laser Amplifier System Based On Self-mode-locked Femtosecond Ti:Sapphire Oscillator

Ultrahigh intensity and ultrashort pulse laser has been becoming one of focus research items in the field of ultrashort pulse laser technology, because it has an important application in many fields, such as X-ray laser, lab celestial bodies physics, ICF, laser particle accelerator, high-intensity field laser and so on.As chirped pulse laser amplification (CPA) is an effective method of getting femtosecond ultra-high laser pulse, it is attracting more and more attention, many countries all over the world have paid many people and money to research it.During studying for Master Degree, I am luck to participate in the item "research on the sub-30fs, terawatt level's laser amplifier system" attributed to the work "research on the high intensity laser physics and ultrafast process" which is imbursed by the national " the ninth five-year plan". The main work I have done are :1. The issue on group velocity dispersion, self phase modulation, Kerr-lens mode-locking and self-starting of laser oscillator has been studied, and the compensation for astigmatic of cavity and for dispersion of self-mode-locked femtosecond Ti:Sapphire oscillator are also analyzed. Based on these, some experiments are developed. After optimizing, lOfs, 82MHz, 800m W pulse train are directly achieved.2. The aberration-free grating stretcher is revised and designed, after optimizing all of the system, the stretching factor of 61552.1 is obtained, the duration of pulse from stretcher is 615.52 ps. A matrix formalism which can be used to analyze the dispersion system conveniently is obtained by introducing a dispersion term based on the ABCD matrix formalism, GVD and TOD of aberration-free grating stretcher are achieved conveniently and truly using the matrix formalism. The formula of calculating the stretching factor is revised, when TOD is considered, the stretching factor of aberration-free grating stretcher can be calculated accurately. This part work is my emphasis.3. Chirped pulse laser amplifying theory is analyzed, and various nonlinear effects in the process of chirped pulse laser amplification are discussed too. Based on these, some measures are given to eliminate them.4. The value of dispersion introduced by grating compressor is calculated using matrixformalism. The issue of dispersion compensation in chirped pulse laser amplifier system is discussed too. In addition, the dispersion compensation for aberration-free grating stretcher is evaluated.5. Some experiment are developed based on the technology of pulse duration measure of femtosecond pulse and single pulse selection from pulse train, some good results are achieved.