Simple method to measure the interaction potential of dielectric grains in a dusty plasma

Journal Article · Wed Sep 15 00:00:00 EDT 2010 · Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print)

DOI:https://doi.org/10.1103/PHYSREVE.82.036401· OSTI ID:21464499

Zhuanhao, Zhang; Ke, Qiao; Jie, Kong; Matthews, Lorin; Hyde, Truell ^[1]

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1. Center for Astrophysics, Space Physics, and Engineering Research, Baylor University, Waco, Texas 76706 (United States)

A simple minimally perturbative method is introduced which provides the ability to experimentally measure both the radial confining potential and the interaction potential between two individual dust particles, levitated in the sheath of a radio-frequency (RF) argon discharge. In this technique, a single dust particle is dropped into the plasma sheath to interact with a second individual dust particle already situated at the system's equilibrium point, without introducing any external perturbation. The resulting data are analyzed using a method employing a polynomial fit to the particle displacement(s), X(t), to reduce uncertainty in calculation. Employing this technique, the horizontal confinement is shown to be parabolic over a wide range of pressures and displacements from the equilibrium point. The interaction potential is also measured and shown to be well described by a screened Coulomb potential and to decrease with increasing pressure. Finally, the charge on the particle and the effective dust screening distance are calculated. It is shown for the first time experimentally that the charge on a particle in the sheath of an RF plasma decreases with increasing pressure, in agreement with theoretical predictions. The screening distance also decreases with increasing pressure as expected. This technique can be used for rapid determination of particle parameters in dusty plasma.

• OSTI ID: 21464499
• Journal Information: Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics (Print), Vol. 82, Issue 3; Other Information: DOI: 10.1103/PhysRevE.82.036401; (c) 2010 The American Physical Society; ISSN 1539-3755
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ARGON
COULOMB FIELD
DIELECTRIC MATERIALS
DISTURBANCES
DUSTS
ELECTRIC DISCHARGES
EQUILIBRIUM
PARTICLES
PLASMA
PLASMA CONFINEMENT
PLASMA SHEATH
POLYNOMIALS
POTENTIALS
RADIOWAVE RADIATION
CONFINEMENT
ELECTRIC FIELDS
ELECTROMAGNETIC RADIATION
ELEMENTS
FLUIDS
FUNCTIONS
GASES
MATERIALS
NONMETALS
RADIATIONS
RARE GASES