Laser-Driven Electron Acceleration In An Inhomogeneous Plasma Channel

New directions in strong laser field physics and related frontier is one of the most important frontier of modern physics and even modern science, it not only has important significance in scientific but also be a important role in promoting of national strategic high technology and interdisciplinary field. The generation of high-order harmonic and attosecond pulse, the propagation of strong laser in the atmosphere, the high gradient electron and ion acceleration by laser-driven, and the generation of new light source, light and physics, fast fire laser fusion and other new concepts of laser fusion and so on. These are the subject of great concern in this field. The interaction between laser and plasma has been studied widely in the fundamental research and technical application, and get a lot of attention from people. In recent years, with the development of ultrashort pulse laser technology, the use of ultrashort laser and plasma interaction electron acceleration to achieve the program has made great progress many theoretical and experimental studies have discussed the laser-driven electron and ion acceleration, then made some progress. Laser wakefield accelerator, the laser beat wave accelerator, and ponderomotive acceler-ation have been developed for this purpose. And the electron acceleration approaching a GeV energy is being achieved. This paper mainly discusses the laser-driven electron accelerate in inhomogeneous plasma channel.The first chapter, we briefly introduces the physical background, including the basic knowledge of plasma and laser, and the characteristic and application of plasma in physics. Then introduced the method how to discuss the interaction between laser and plasma and the generation of plasma channel.In the chapter 2, we analyze the electron acceleration which irradiated by a plane electromagnetic wave in a plane inhomogeneous plasma. Starting from the base func-tions,we get the dynamics functions of electron. By adjusting the parameters, the differ-ences between homogeneous and inhomogeneous are obtained. The we find the influence in different inhomogeneous distribution type. To confirm the theoretical predictions, nu-merical solutions of dynamics functions are given. We plot the oscillation of electron in different plasma channel. Three type of inhomogeneous charge density distribution are discuss:i. e., with linear, parametric and cosine density profiles. We find that the de-veloping of instability and acceleration of electron in inhomogeneous ion channel is more efficient than that in homogeneous ion channel. Furthermore, comparing with the homo-geneous ion channel, electron in the inhomogeneous ion channel can gain more energy. And the shorten of the accelerating length and the enhancement of the energy gain in inhomogeneous ion channel depend on polarization angle and inhomogeneous parameters.The third chapter we focus on discussing the developing of the instability for electron acceleration and electron energy gain from laser wave in both homogeneous and inhomo-geneous non-planar cylindrical plasma channel. Starting from the base functions, we get the dynamics functions of electron. By adjusting the parameters, the differences between homogeneous and inhomogeneous are obtained. Then we find the influence in different inhomogeneous distribution type. To confirm the theoretical predictions, numerical so-lutions of dynamics functions are given. We plot the oscillation of electron in different plasma channel. Three type of inhomogeneous charge density distribution are discuss:i. e., with linear, and parametric density profiles. We find that the significant enhancement of the parametric amplification for electron acceleration in cylindrical plasma channel is observed. The instability (i.e., electron acceleration) in cylindrical plasma channel devel-ops more quickly and strongly than that in planar two-dimensional plasma channel. Then, enhancing of energy gain and shorten of acceleration length in cylindrical plasma channel are observed. For the cylindrical plasma channel, electron acceleration in inhomogeneous plasma channel is more efficient than that in homogeneous plasma channel. That is, the electron in the inhomogeneous plasma channel can gain more energy from laser and the acceleration length can be shorten by adjusting the width of laser and the inhomogeneous charge density distributions.In the fourth chapter, we summarize the main results and give an outlook of the future in this field.