arXiv subjects

Danijela D. Sijacic

Publications and source records attributed to Danijela D. Sijacic.

3 recordsLinked to original sources

arXiv2004

Oscillations in DC driven "barrier" discharges: numerical solutions, stability analysis and phase diagram

A short gas discharge layer sandwiched with a semiconductor layer between planar electrodes shows a variety of spatio-temporal patterns. The paper focusses on the spatially homogeneous spontaneous oscillations while a DC voltage is applied; the results on these homogeneous oscillations apply equally to a planar discharge in series with any resistor with capacitance. We define the minimal model, identify its independent dimensionless parameters and then present results of the full time-dependent numerical solutions of the model as well as of a linear stability analysis of the stationary state. Full numerical solutions and the results of the stability analysis agree very well. The stability analysis is then used for calculating bifurcation diagrams. We find semi-quantitative agreement with experiment for the diagram of bifurcations from stationary to oscillating solutions as well as for amplitude and frequency of the developing limit cycle oscillations.

physics.plasm-ph↗

arXiv2003

Period doubling in glow discharges: local versus global differential conductivity

Short planar glow discharges coupled to a resistive layer exhibit a wealth of spontaneous spatio-temporal patterns. Several authors have suggested effective reaction-diffusion-models to explore similarities with other pattern forming systems. To test these effective models, we here investigate the temporal oscillations of a glow discharge layer coupled to a linear resistor. We find an unexpected cascade of period doubling events. This shows that the inner structure of the discharge is more complex than can be described by a reaction-diffusion-model with negative differential conductivity.

nlin.PS↗

arXiv2003

Transition from Townsend to glow discharge: subcritical, mixed or supercritical

The full parameter space of the transition from Townsend to glow discharge is investigated numerically in one space dimension in the classical model: with electrons and positive ions drifting in the local electric field, impact ionization by electrons ($α$ process), secondary electron emission from the cathode ($γ$ process) and space charge effects. We also perform a systematic analytical small current expansion about the Townsend limit up to third order in the total current that fits our numerical data very well. Depending on $γ$ and system size pd, the transition from Townsend to glow discharge can show the textbook subcritical behavior, but for smaller values of pd, we also find supercritical or some intermediate ``mixed'' behavior. The analysis in particular lays the basis for understanding the complex spatio-temporal patterns in planar barrier discharge systems.

cond-mat.mtrl-sci↗