Electron Acceleration in Wakefield and Supra-Bubble Regimes by Ultraintense Laser with Asymmetric Pulse

Abstract

Electron acceleration in plasma driven by circular polarized ultraintense laser with asymmetric pulse are investigated analytically and numerically in terms of oscillation-center Hamiltonian formalism. Studies include wakefield acceleration, which dominates in blow-out or bubble regime and snow-plow acceleration which dominates in supra-bubble regime. By a comparison with each other it is found that snow-plow acceleration has lower acceleration capability. In wakefield acceleration, there exists an obvious optimum pulse asymmetry or/and pulse lengths that leads to the high net energy gain while in snow-plow acceleration it is insensitive to the pulse lengths. Power and linear scaling laws for wakefield and snow-plow acceleration respetively are observed from the net energy gain depending on laser field amplitude. Moreover, there exists also an upper and lower limit on plasma density for an effective acceleration in both of regimes.

Effects of laser waveform on the generation of fast electrons in laser–solid interactions

“…Besides the parameters described above, the laser waveform is one of the important parameters affecting the interaction between laser and solid-density plasma. Theoretical and experimental results have shown that the waveform, the rising edge, and the asymmetry of the laser pulse have an influence on the wake field electron acceleration [16][17][18][19] , the generation of terahertz radiation [20] , and electron acceleration from vacuum [21] . With the development of laser technology, including the pulse-shaping technology such as programmable spatial light modulators, acousto-optic modulators, moving mirrors, deformable mirrors, and plasma optics, it is now possible to achieve asymmetric laser waveforms in experiments [22][23][24][25][26] .…”