Energetic electron bunch generation by an intense laser pulse

In this paper, three-dimensional particle simulation results show a generation of high-energy micro-electron bunch by using an intense short-pulse laser composed of a linear combination of a TEM10 mode and a TEM01 mode in vacuum. The longitudinal electric field of this laser accelerates electrons in the longitudinal direction, and the electron beam size becomes a few micrometers. In this paper we found that this electron bunch has several energy spectrum peaks and the energy spread is smaller than 10% in each spectrum peak. If the laser intensity is enough high, the electron energy is proportional to a(0) and the electron energy is not influenced much by the variation of the initial electron energy. The simulation results are compared with the scaling law, and the scaling results coincide well with the simulation results.