Electron bunch acceleration and trapping by ponderomotive force of an intense short-pulse laser
Electron ponderomotive acceleration in a vacuum by a short-pulsed laser of TEM (1, 0) + TEM (0, 1) mode is studied in this paper using a 3-dimensional (3D) particle simulation. It was found that the laser can trap electrons in transverse and accelerate them with the longitudinal ponderomotive force at the same time. Through this electron trapping and acceleration scheme of TEM (1, 0) + TEM (0, 1) mode laser, the electron bunch is confined well in transverse and compressed remarkably in longitudinal. Therefore, a high energy, high density, and low emittances electron bunch is generated. For example, the result shows that for a laser with intensity of a0 = eE0 /m[omega]c = 10, the laser spot size of w0 = 15[lambda], and the laser pulse length of Lz = 10[lambda], the maximum energy gain reaches 301 MeV and the average energy 57.7 MeV. The electron bunch transverse radius is about 350[lambda] and the longitudinal size about 20[lambda]. The property of this accelerated bunch is improved compared with that generated by the laser of TEM (0, 0) mode.(Received September 1 2004)
(Accepted October 25 2004)
Key Words: Electron bunch; Laser electron acceleration; Ponderomotive acceleration.
c1 Address correspondence and reprint requests to: Shigeo Kawata, Department of Electrical and Electronic Engineering, Utsunomiya University, Yohtoh 7-1-2, Utsunomiya 321-8585, Japan. E-mail: email@example.com