Interaction force between two finite-size charged particles in weakly ionized plasma

Abstract

The results of numerical studies of the interaction forces between two finite-size charged spherical conductive particles embedded into weakly ionized strongly collisional isothermal plasma-like medium are presented. The studies are performed for the case of particles with fixed electric charge under the assumption that particles do not absorb electrons and ions from the surrounding plasma (colloidal particles) as well as for particles charged by plasma currents (grains). In the first case the Poisson-Boltzmann model was used and in the second the dynamics of grain charging is described in the drift-diffusion approximation. It is shown that at the large distances the interaction force between colloidal particles has the Debye screened asymptotic while for the grains the Coulomb-like behavior is observed. The dependence of the grain charge collected due to the plasma particle absorption on the distance between two grains is studied. The possibility of introducing effective Coulomb description of finite-size grain interaction in weakly ionized strongly collisional plasma is discussed.

Effective charge of a macroparticle in a non‐isothermal plasma within the Poisson–Boltzmann model

“…This conclusion is in agreement with the numerical results for an isothermal plasma. [13,18] The distance R grows considerably with . It is explained by the fact that in a non-isothermal plasma the validity of assumption (7) and the applicability of linear approximation for the exponential functions in the right-hand side of Equation (13) are different for electrons and ions.…”

“…Since then, numerous approximate analytical expressions and numerical calculations for the effective charge in different geometries have been reported, see for example, Refs. [12][13][14][15][16][17][18]. All the above-mentioned papers consider an isothermal plasma-like medium.…”

Dynamic properties of strongly coupled dusty plasmas with particles of finite dimensions

“…For point‐like dust particles, the interaction potential is well known and is customarily chosen in the form of the Yukawa potential, whereas for particles of finite dimensions the situation looks far more complicated. The interaction of two isolated spherical dust particles in an equilibrium plasma was studied in based on the stress tensor and within the framework of the Poisson–Boltzmann model. A completely analogous approach, based on the generalized Poisson–Boltzmann equation, was initially developed for a partially ionized medium, and then fruitfully applied to a dusty plasma .…”

Specific Features of Microwave Methods for Dusty Plasma Diagnostics. I. Dielectric Permittivity, Refractive and Absorption Indices

“…The dusty plasma (complex, colloidal plasma) is an ionized gas that contains macroscopic (micronand submicron-sized) charged particles [9][10][11][12][13][14][15]. The interest in a dusty plasma is associated with its wide spread in the nature (atmosphere, outer space, and so forth) and in technological plasma installations (etching, sputtering, thermonuclear, and others).…”

“…As a rule, plasma particles (macroscopic particles) are charged negatively, and their charge can reach a value of up to 10 5 times the electron charge. The presence of charged dust particles not only changes the balance between the electron and ion concentrations, thus affecting the propagation of plasma oscillations, but also results in the emergence of new low-frequency waves [9][10][11][12][13][14][15].…”