Yoctosecond Pulse Obtained By Collision Of High-energy Electron With Ultra-short Ultra-intensive Laser Pulse

Since the birth of the first laser in the world,various laser technologies have emerged continuously.Among them,chirped pulse amplification technology increases the laser pulse intensity to 10²²W/cm²,making the laser pulse width reach femtosecond or even attosecond level.When such a high-intensity laser pulse collides with a high-energy electron,a secondary radiation pulse with higher intensity,shorter pulse width,better coherence and tunable is generated.This radiation pulse can be used as a time scale for observing the internal reactions of microscopic particles such as atoms,and can also use its unique‘water window’band to non-destructively probe the interior of cells.In order to make better use of the secondary radiation pulse,the interaction between high-energy electron and ultra-short ultra-intense laser pulse needs to be deeply studied.This paper is mainly based on the collision model of high-energy electron and ultra-short ultra-intense laser pulse,combined with the electrodynamics formula and energy conservation formula,and simulates various situations through MATLAB software,and then studies the motion state in the collision process of high-energy electron and laser.In addition,the power spectrum,spatial spectrum and spectrum of the secondary radiation pulse under different observation angles,primary laser phases,and laser intensities are also studied.In the last chapter of the paper,the suitable laser pulse parameters for generating yoctosecond radiation pulse are searched,and its radiation characteristics are studied.Through careful analysis of the obtained results,it is first found that the trajectory of the high-energy electron in the ultra-short ultra-intense laser pulse is helical,and the longitudinal velocity of the electron first decreases and then increases.Secondly,it is found that the best observation angle of the secondary radiation pulse is consistent with the initial phase of the ultrashort and super intense laser pulse.The greater the difference between the observation angle and the initial phase of the laser pulse,the lower the peak power of the secondary radiation pulse and the wider the pulse width.In addition to the observation angle and the initial phase of the laser pulse,the laser pulse intensity also has an important influence on the secondary radiation.The greater the laser pulse intensity,the greater the peak power of the secondary radiation pulse and the narrower the pulse width.Finally,it is found that when the normalized intensity of the laser pulse is a₀=90,the yoctosecond radiation pulse can be obtained by observing the secondary radiation pulse at the best observation angle.