Plasma Polarization Around Dust Particle in an External Electric Field

Abstract

The effect of plasma polarization around a negatively charged dust particle is investigated with the help of Monte Carlo simulation of ion trajectories in the electric field of the dust particle and an external electric field. The induced dipole moment of such a system was estimated in a wide range of dust particle and plasma parameters. It is shown that the dipole moment is very large, and has a non-monotonous dependence on the external electric field. For a small external electric field, it weakly depends on the charge of the dust particle. The dipole moment reduces with the decrease of ion mean free path.

Sound speed and diffusion in 2D Yukawa liquids: Effect of dipole–dipole interaction

“…The considered range of the plasma parameters is Γ = 20–160, and k S = 1.0−2.0. In general, Γ d is not independent of Γ. Sukhinin et al , showed that the ion cloud focused as a result of the external electric field and attraction by the charged dust particle can have a volume charge ∼ Q /2 placed at a distance ∼ λ S /2 from the dust particle. Therefore, we consider Γ d in the range 0–Γ d (= 0.2 × Γ).…”

Potential distribution around the charged particle in the collisional weakly ionized plasma in an external electric field

“…In the weakly collisional conditions Q ∞ comes to zero, η ≈ 0.5, and second term consists with the result of the kinetic approach [4]. In the paper of Sukhinin et al [8] the total dipole moment inside calculation region was calculated by the molecular dynamic for the mean free path length of ions l i = 10λ D and l i = 2λ D . The last case can be compared with the present results taking into account finite size of the calculation region.…”

“…Taking into account (8) and (10) we have Figure 2. The dependence of the reduced dipole moment on a size of the integration layer for E ′ = 1 (a) and on the reduced external electric field for L = 10λ D (b); line is hydrodynamic approach, triangles and squares are molecular dynamic results [8].…”

“…where E ′ = |k E |λ D /2 is the reduced electric field (according [8]) and l ′ = l i /λ D . The dependence of the reduced dipole moment P ′ = P/(Qλ D ) on a size of the integration layer is presented in figure 2(a) for E ′ = 1 and l ′ = 2.…”

“…The dependence of the reduced dipole moment P ′ = P/(Qλ D ) on a size of the integration layer is presented in figure 2(a) for E ′ = 1 and l ′ = 2. The figure 2(b) exhibits the dependence of the reduced dipole moment on the reduced external electric field calculated by equations (17), (18), and (21) for the calculation region length L = 10λ d and the results of [8]. The hydrodynamic approach underestimates a dipole moment for distances less or comparable with ion mean free path length, but gives good accordance with the molecular dynamic results at the distance from the particle as low as L/2 = 2.5l i .…”