Observation of intermittent states and nonlinear wave-wave interaction in neon glow discharges

In the plasma of a neon glow discharge under certain conditions two waves (s- and p-wave) are known to exist simultaneously. The transition region between these two kinds of waves is experimentally investigated in the space of plasma parameters. An intermittent behaviour of s- and p-waves dynamics is proved by the analysis of the recorded spatio-temporal patterns of light emitted by plasma. The experimental data are analyzed with the biorthogonal decomposition (BOD) and the empirical mode decomposition (EMD), respectively. The wave states can be described by means of a coupled system of amplitude equations resulting from a hydrodynamic plasma model. Comparison of experimental data and theoretical predictions shows satisfactory agreement. The discrepancies are discussed.