Topic/Type: 1.3 High intensity Laser Plasma Interaction, Poster

Numerical stability analysis of relativistic solitons in 1D and 2D geometry

G. Lehmann, E.W. Laedke, K.H. Spatschek

Institute for Theoretical Physics I, Heinrich-Heine-University, Duesseldorf, Germany

The creation of slow moving relativistic solitary structures
from high intensity laser radiation interacting
with plasma has been demonstrated in various experiments
and simulations. Considerable amounts of the laser
radiation, up to 40%, are predicted to become trapped
in these cavities.

An important question is the stability of the structures,
and in case of instability, the characteristic life-times.
Here we concentrate on numerical techniques with applications
to solitons.

The solitons are stationary
solutions of the Maxwell-fluid equations and model
trapped radiation with relativistic intensities.
The structure of the most unstable mode and its
growth rate are first determined depending on polarization
within a one-dimensional (1D) model.
Different types of instabilities are found and quantified.
Nonlinear 1D simulations show
excitation of a wake-field and subsequent
wave-breaking as part of appearing instabilities.
In order to explain the instability of the excited
electrostatic wave, we refine existing wave-breaking
criteria.

To allow for transversal perturbations, we discuss
the stability of circular polarized solitons in 2D geometry.
All studied relativistic solitons turn out to suffer from
transversal instability.
It is found that the transversal instability is growing
much faster than the longitudinal instability.