Experimental investigation of dissipative solitons and other self-organised patterns in dielectric barrier discharge systems

对非线性耗散系统中自组织模式的理解是近年来自然科学的重大挑战之一。特别是具有粒子样行为的局部孤立结构的出现，是许多物理、化学和生物系统的共同特征。这些结构被称为耗散孤子。本课题将研究平面介质阻挡放电系统中以电流细丝形式出现的耗散孤子。计划任务包括细丝动态的研究，例如细丝运动，细丝稳定性，特别是在碰撞过程中，以及细丝的产生和湮灭。此外，还应讨论具有不同灯丝行为的制度之间的分岔。因此，非线性动力学和模式形成的观点以及等离子体物理的需要被铭记。因此，在宏观层面上的理解，非常常见的推理，以及在等离子体物理模型的水平上，允许实验和理论数据的定量比较是渴望的。因此，除了传统的高速相机对细丝发射光的观测外，介质屏障表面电荷的测量系统将在灵敏度、空间分辨率和时间分辨率上得到提高。对于数据解释，将使用成像技术和统计数据分析方法。该项目的工作进一步深入了解了弱电离低温等离子体中自组织模式的机制，并有助于理解耗散系统中的自组织。

The understanding of self-organised patterns in nonlinear dissipative systems is one of the great challenges in recent natural sciences. Especially the appearance of well localised, solitary structures with particle like behaviour is a common feature of many physical, chemical and biological systems. These structures are known as dissipative solitons. In this project dissipative solitons appearing in a planar dielectric barrier discharge system in the form of current filaments will be investigated. The scheduled tasks comprise investigations of the filament dynamic, e.g. filament movement, the filament stability, especially during collision processes, and generation and annihilation of filaments. Also the bifurcations between regimes with different filament behaviour shall be addressed. Thereby the point of view of nonlinear dynamics and pattern formation as well as the needs of plasma physics are kept in mind. Hence, an understanding on the level of macroscopic, very common reasoning as well as on the level of plasma physical models allowing quantitative comparison of experimental and theoretical data is aspired. Therefore, beside the traditional observation of the emitted light of filaments with high speed cameras, a measurement system for surface charges on the dielectric barriers will be improved in sensitivity, spatial, and temporal resolution. For the data interpretation both imaging techniques as well as statistical data analysis methods will be used. The work in this project gives a further insight into the mechanisms of self-organised patterns in weakly ionised low temperature plasmas in particular and contributes to the understanding of self-organisation in dissipative systems in general.