Volume 85, Number 2, January 2009
Article Number 25003
Number of page(s) 4
Section Physics of Gases, Plasmas and Electric Discharges
Published online 22 January 2009
EPL, 85 (2009) 25003
DOI: 10.1209/0295-5075/85/25003

Mode conversion of large-amplitude electromagnetic waves in relativistic critical density plasmas

T. C. Pesch and H.-J. Kull

Institute of Theoretical Physics A, RWTH Aachen University - Templergraben 55, 52056 Aachen, Germany, EU

received 14 November 2008; accepted in final form 18 December 2008; published January 2009
published online 22 January 2009

The propagation of linearly polarized large-amplitude electromagnetic waves in critical density plasmas is studied in the framework of the Akiezer-Polovin model. A new mechanism of mode conversion is presented. The well-known periodic solutions are generalized to quasiperiodic solutions taking into account additional electrostatic oscillations. Nearly periodic circle-like solutions are found to be stabilized by intrinsic mode coupling whereas for nearly periodic eight-like solutions an effective mode conversion mechanism is discovered. Finally, the modulation timescales are considered.

52.27.Ny - Relativistic plasmas.
52.38.-r - Laser-plasma interactions.
52.35.Mw - Nonlinear phenomena: waves, wave propagation, and other interactions (including parametric effects, mode coupling, ponderomotive effects, etc.).

© EPLA 2009