The excitation of large amplitude plasma oscillations by the ponderomotive force exerted by a short electromagnetic (e.m.) radiation pulse on the electrons, is described within a one-dimensional, relativistic, cold plasma model. The quasistatic approximation, which assumes that the fluid variables follow adiabatically the temporal evolution of the field variables, is assumed to be valid. For a fixed rectangular profile of the e.m. wavepacket, travelling with group velocity vg<c, the analytical solution of the problem is obtained. It is shown that, after the transit of the pulse, the coherent longitudinal electric field (travelling with phase velocity vφ=vg) can reach values higher than EMAXst=√2(mecωpe/e)(γφ-1)1 2, where γφ=(1-v2φ/c2)-1 2, up to EMAX=√2(mecωpe/e)(γ2φvφ/c) (3-v2φ/c2-√5-2v2φ/c2+v4φ/c4)1 2. However, this is only a transient dynamics which leads inevitably to the wavebreaking at a distance of approximately one wavelength from the beginning of the pulse. Actually, only for E<EMAXststationary plasma oscillations can be sustained. © 1993.
|Pages (from-to)||456 - 461|
|Number of pages||6|
|Journal||Physics Letters, Section A: General, Atomic and Solid State Physics|
|Publication status||Published - 22 Feb 1993|
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
Dalla, S., & Lontano, M. (1993). On the maximum longitudinal electric field of a large amplitude electron plasma wave excited by a short electromagnetic radiation pulse. Physics Letters, Section A: General, Atomic and Solid State Physics, 173(6), 456 - 461. https://doi.org/10.1016/0375-9601(93)90156-T