The Research On Laser Amplifier System Of Titanium-doped Sapphire Femtolaser

As ultra-higher intensity and ultra-short pulse has an important application in the field of forward position research ,such as X-ray laser, lab celestial bodies physics, ICF, laser-particle accelerator, high-intensive field laser physics and so forth ,it has grown a focus research item. And as chirped pulse amplification(CPA) is an effective method to get the ultra-higher intensity and ultra-short pulse width ,it attracts more attention, and all over the world have put much study on it. In the period of my study, I participate in the work of the "the research on less than 30-fs,terawatt level's laser system",and its main content is that as below: 1. Introduced the development of the technique of ultra-high intensity and ultra- short pulse ,and its emphases is that the principle ,developnient and makeup of the chirped pulse amplification. 2. Analyzed and researched each part of the stmcture and principle of the amplification system. To the pulse seed source of the amplification system--- Titanium-doped sapphire(Ti:S) femtolaser, made a thorough research on the principle and structure ,and made a detailed analysis on the group delay disperse, self-phase modulation and self-mode locked, and then got the parameters and relations about the steady mode-locked of our laser and had a mode-locked pulse output : IOfs,800mW,82MHz.; Introduced the history of the development of stretcher of amplification system, presented the advantage and disadvantage of all the types stretcher , made a thorough analysis on the compressor ,and then made a thorough research on the stretcher characteristic at last made a introduction to the stretcher in our experiment equipment and got a 600-ps stretched pulse width ,stretcher rate~6X l04To the amplification of CPA, made a analysis on the gain saturation with the laser amplification principle, and then got a relation between the gain saturation and numbers of pass ,which is important to the actual amplification system. By analyzing the evolvement of the beam diameter with the number of pass in the amplification system, gave a method of reducing gain saturation. Through making a thorough study on gain-narrowing, we introduced a Gauss Filter which reshaped the spectrum in reducing gain-narrowing ,and found that it is good for reducing gain-narrowing effect. Made an analysis on the compressor's structure and principle, and presented our actual compression scheme. 3. The time-sequence measuring and single pulse selecting are introduced. And through the actual measuring and controlling ,mastered this technology.