Electron Beam And X-ray Source Driven By Ultrafast Laser

The rapid development of ultrafast laser technology has impacted the science and technology in every way since the 1980 s.High quality particle and radiation sources could be generated from the interaction of ultrafast laser and plasma.These sources are very useful for fast ignition inertial confinement fusion,fundamental scientific research,industry and many other areas.For that they have drawn great attention and been studied widely.This dissertation presents the related research contents which have been accomplished during the PhD study and is organized as follow.The first part is the introduction which lays the foundation of the whole thesis.In this part the laser-plasma interaction are reviewed,including the physical mechanisms and phenomena.After that the interaction of ultra intense laser and underdensed plasma and laser wake-field acceleration is summarized.The interaction of laser and overdensed plasma is presented at the last of this part,including physical pictures and laser absorption mechanisms.Chapter 2 presents the collimated x-ray sources driven by ultrafast lasers.First a glimpse of the x-ray sources is presented.Following is the overview of the laser-based x-ray sources,including K-alpha hard x-ray source,the Betatron radiation and the inverse Compton scattering(ICS)source.The properties of Betatron radiation and ICS source are deduced based on a synchrotron radiation model.Comparison of these two sources is made for realistic parameters.A new method to enhance the ICS radiation is proposed,primary experimental results verified the feasibility of the proposed method.Chapter 3 presents the K-alpha hard x-ray source from the interaction of a high repetition rate laser with solid target.This hard x-ray source has the merits of small source size high average photon flux.The average radiated power is the highest of this kind of sources as to our knowledge.High quality imaging tests are demonstrated.Chapter 4 is about the collimated electron beam along the target surface from the interaction of sub-picosecond laser with a disk solid target.The target surface electron beam is highly directional and with large beam charge,suitable for fast ignition scenario as it could offer high energy coupling efficiency to the pre-compressed fuel core.Chapter 5 presents the ultrafast x-ray application platform constructed in IOP,CAS.Based on a kHz high power laser,this system is built for ultrafast time-resolved x-ray diffraction,high quality hard x-ray imaging and x-ray spectroscopy.Conclusion is drawn at the end of the dissertation,as well as perspectives of the related researches.