RESUMEN
The analysis of a one-dimensional two-fluid hydrodynamic model with relativistic electrons and nonrelativistic ions shows that the propagation of a nonlinear plasma wave is accompanied by a steady currentless plasma drift. Ions, due to their larger mass, appear to be the main carriers of the average momentum of the plasma wave. Two examples of nonlinear plasma waves generated by moving sources (short laser pulses and electron bunches) are analyzed to show details of the energy and momentum conservation laws.
RESUMEN
The propagation of a short intense laser pulse in the femtosecond range in a hollow metallic waveguide gives rise to heating of the metallic wall. The temperature of the degenerate electron gas in the wall is increased during the pulse duration and this heating affects the propagation and dissipation of the laser pulse. Analytical and numerical analysis shows that, as the dissipation is increased, the leading edge of the pulse decreases more slowly than the rear, resulting in a pulse shortening.
RESUMEN
A new physical effect of a plasma channel formation by the ponderomotive force of a wakefield generated by a laser pulse with a length of the order of the electron plasma wavelength is discussed. For a narrow pulse, wherein the width is less than c/omega(pe) ( omega(pe) and c are the plasma frequency and light velocity, respectively), the channel has an annular form with on-axis density maximum. The depth of the channel increases with the distance from the pulse until the phase mixing arises and the wake starts to break. The linear fluid theory is used to obtain the scaling for wave-breaking conditions. The results of numerical simulations for high intensity laser pulses are in good agreement with theoretical predictions.