Production of femtosecond single-bunched electrons by laser wakefield acceleration

Design of a femtosecond single-bunched electron linac is described based on laser wakefield acceleration (LWA) for study of solid-state physics and chemistry. In this acceleration scheme, a short laser pulse drives plasma waves. The potential of the waves then accelerates charged particles. The bunch length of the accelerated particles is proportional to the plasma wavelength. The present design using a 100 fs-2 TW T-3 laser gives a 30 MeV-10 pC single bunch with an rms bunch length of less than 10 fs. It accelerates and compresses a high-current beam from an rf photocathode. Use of a chicane and a plasma klystron is proposed for the compression. Some practical problems concerning the design are also presented. (C) 1997 Elsevier Science B.V.