Characterizing the Chaos in a Steady-State Plasma Discharge

Chaos transited from period doubling in plasmas is characterized with several methods. Waveform and fast Fourier transform confirm that the signal is nonperiodic. One dimensional unimodal like structures of the return maps of next amplitude with peak and valley values are obtained to illustrate the deterministic feature. Numerical experiments on one-dimensional logistic map are carried out to simulate the experimental results. Positive Lyapunov exponent 1.33 ± 0.10, directly calculated from the experimental data, provides the evidence that the signal is chaotic. Correlation dimension 2.75 ± 0.05 demonstrates that this signal is decreased to a low dimensional attractor in the plasma.