Self‐modulation of short intense laser pulse: Opportunities for wake‐field accelerator

Comparative analytical and numerical study of the laser pulse self‐modulation and the plasma wake‐field excitation is introduced for the cases when the self‐modulation is triggered by the relativistic self‐focusing and when it is initiated by the second frequency‐shifted weak‐intensity laser pulse. Both cases of a homogeneous plasma and a preformed plasma channel are considered. Basing on the obtained results, the new scheme of stimulation (by a second weak‐intensity laser pulse) and maintaining (using a preformed plasma channel) of the strong wake‐field excitation is proposed. This scheme gives an opportunity to provide enhanced acceleration at the distances of tens of the Reyleigh lengths and to obtain gigaelectronvolt energy of the accelerated electrons using the present‐day laser technology.