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We present the results of an experimental and analytical study of the structural and dynamic properties of a monolayer consisting of dust grains in an electrostatic trap in an RF discharge plasma. The possibility of forming a monolayer with an isotropic distribution for interparticle distance and kinetic energy of particles in the structure has been experimentally shown. Isotropy has crucial importance for the study of various processes in such systems, including the kinetics of phase transitions, the formation of directed flows, wave propagation, and others. [ABSTRACT FROM AUTHOR]

Experimental data on the motion of a single colloidal particle in a trap in the near-electrode layer of an RF-discharge plasma are analyzed. The experiment was conducted with three types of colloids: uncoated melamine-formaldehyde particles, melamine-formaldehyde particles with a thin copper coating, and Janus particles partially coated with iron. The colloids were exposed to a flat wide laser beam, allowing them to be visualized and their kinetic energy changed. To analyze the motion of particles, the functions of their dynamic entropy of the first intersection were constructed and the region of particle localization and the fractal dimension of their trajectories were found. The results obtained indicate a significant difference between colloids of different types, as well as the evolution of their motion with a change in kinetic energy. It is shown that the fractal dimension of the trajectories of all types of particles is fractional and decreases with an increase in their kinetic energy. [ABSTRACT FROM AUTHOR]

We present the results of an experimental and analytical study of the structural and dynamic properties of a monolayer consisting of dust grains in an electrostatic trap in an RF discharge plasma. The possibility of forming a monolayer with an isotropic distribution for interparticle distance and kinetic energy of particles in the structure has been experimentally shown. Isotropy has crucial importance for the study of various processes in such systems, including the kinetics of phase transitions, the formation of directed flows, wave propagation, and others.

We present the results of an experimental study of the behavior of a colloidal plasma system formed by copper-coated and uncoated polymer particles under the action of laser irradiation. A comparative study of particle velocity distribution profiles depending on the power of the pushing laser was conducted. In the case of uncoated melamine-formaldehyde (MF) particles, we observed the well-known action of light pressure, causing shear stress in the colloidal plasma structure and leading to the occurrence of a laminar flow within the affected area. For the copper-coated MF particles, we revealed some additional patterns of behavior for the dust particles, i.e., kinetic temperature growth due to laser radiation absorption by the copper coating, as well as the appearance of chaotic particle motion. We believe that this happens due to the existence of defects in the coating, causing asymmetric heating of the particles, which in turn leads to chaotic deviations of the photophoretic force pushing the particles in different directions.

We present the results of an experimental study of the behavior of a colloidal plasma system formed by copper-coated and uncoated polymer particles under the action of laser irradiation. A comparative study of particle velocity distribution profiles depending on the power of the pushing laser was conducted. In the case of uncoated melamine-formaldehyde (MF) particles, we observed the well-known action of light pressure, causing shear stress in the colloidal plasma structure and leading to the occurrence of a laminar flow within the affected area. For the copper-coated MF particles, we revealed some additional patterns of behavior for the dust particles, i.e., kinetic temperature growth due to laser radiation absorption by the copper coating, as well as the appearance of chaotic particle motion. We believe that this happens due to the existence of defects in the coating, causing asymmetric heating of the particles, which in turn leads to chaotic deviations of the photophoretic force pushing the particles in different directions. [ABSTRACT FROM AUTHOR]

The motion of particles in a complex (dusty) plasma agitated by a shock wave was resolved with a high-speed video camera. The shock melted the initially crystalline monolayer. Macroscopic parameters such as number density, kinetic temperature, and flow velocity were determined. The shock caused a 30-fold jump in kinetic temperature. The width of the shock front was found to be on the order of the interparticle distance. [ABSTRACT FROM AUTHOR]