PARAMETRIC EXCITATION AND HIGHER-ORDER MODE COUPLING EFFECTS IN PLASMAS

Parametric excitation [wherein a Langmuir oscillation at (ω, k) simultaneously drives an ion-acoustic mode at (ω′, k′), one sideband Langmuir oscillation at (ω -ω′, k - k′), and possibly another at (ω + ω′, k + k′)] is considered. Steady-state solutions are found for these systems in various limits, taking into account contributions which are third order and higher in the mode fields. Connections with experiment are discussed.