Reaction-Diffusion Equation with Stationary Wave Perturbation in Weakly Ionized Plasmas

Abstract

The influence of external harmonic forcing in nonlinear chaotic systems is a subject of active investigation, chiefly in low-dimensional dynamical systems, but fewer results are available for high-dimensional systems like plasmas. In this paper, we consider a theoretical model for a weakly ionized plasma, in which the following effects are taken into account: (i) ambipolar diffusion; (ii) the inflow of plasma particles through ionization processes; (iii) the outflow of plasma particles due to recombination. The spatiotemporal patterns of the resulting nonlinear system, as revealed by numerical integration of the reaction-diffusion partial differential equations, can be partially or totally suppressed through the action of acoustic waves forming stationary patterns in the plasma container. These suppression effects are quantitatively investigated by a number of numerical diagnostics like the average Lyapunov exponents and spatial correlation function. Suppression of spatiotemporal chaos can be achieved through adequate choices of amplitude and frequency of the applied waves.