Laser parameters affecting the asymmetric radiation of the electron in tightly focused intense laser pulses

Abstract

The nonlinear radiation of the electron is a distinctive feature of the action of tightly focused linearly polarized lasers. In this paper, from the perspective of radiation symmetry, the effect of laser parameters on the electron radiation power in the time domain is studied systematically. In the direction of maximum radiation, an asymmetric bimodal structure is found in the time domain. For this special structure, an explanation is given based on the electron dynamics perspective. The structure is compared with the symmetric bimodal structure in the classical theory. The increase in laser intensity, while significantly increasing the radiated power of the electron, exacerbates the asymmetry of electron radiation. The variation of the initial phase of the laser leads to a periodic variation of the electron motion, which results in a periodic extension of the electron spatial radiation with a period of π. Moreover, the existence of jump points with a phase difference of π in the range from 0 to 2π is found. The increase in pulse width reduces the radiated power, extends the radiation range, and alleviates the radiation asymmetry. Results in this paper contribute to the study of electron radiation characteristics in intense laser fields.