Dynamics of dust in a plasma sheath with a magnetic field was investigated using a single particle model. The result shows that the radius, initial position, initial velocity of the dust particles and the magnetic fie...Dynamics of dust in a plasma sheath with a magnetic field was investigated using a single particle model. The result shows that the radius, initial position, initial velocity of the dust particles and the magnetic field do effect their movement and equilibrium position in the plasma sheath. Generally, the dust particles with the same size, whatever original velocity and position they have, will locate at the same position in the end under the net actions of electrostatic, gravitational, neutral collisional, and Lorentz forces. But the dust particles will not locate in the plasma sheath if their radius is beyond a certain value.展开更多
Our experiment shows that the dust grains, suspended on the edge of the sheath of a radio-frequency discharge, undergo a contraction when switching a vertical magnetic field on, and an expansion when switching the mag...Our experiment shows that the dust grains, suspended on the edge of the sheath of a radio-frequency discharge, undergo a contraction when switching a vertical magnetic field on, and an expansion when switching the magnetic field off. We call this kind of magnetic field "transient magnetic field". A primary analysis is proposed for the phenomenon.展开更多
Induced charge of a spherical dust particle on a plasma-facing wall was investigated analytically, where non-uniform electric field was applied externally. The one-dimensional nonuniform electrostatic potential was ap...Induced charge of a spherical dust particle on a plasma-facing wall was investigated analytically, where non-uniform electric field was applied externally. The one-dimensional nonuniform electrostatic potential was approximated by the polynomial of the normal coordinate toward the wall. The bipolar coordinate was introduced to solve the Laplace equation of the induced electrostatic potential. The boundary condition at the dust surface determines the unknown coefficients of the general solution of the Laplace equation for the induced potential. From the obtained potential the surface induced charge can be calculated. This result allows estimating the effect of the surrounding plasma, which shields the induced charge.展开更多
基金supported by National Natural Science Foundation of China(No.10605008)the Scientific Research Program of the Education Department of Liaoning Province(No.2005069)
文摘Dynamics of dust in a plasma sheath with a magnetic field was investigated using a single particle model. The result shows that the radius, initial position, initial velocity of the dust particles and the magnetic field do effect their movement and equilibrium position in the plasma sheath. Generally, the dust particles with the same size, whatever original velocity and position they have, will locate at the same position in the end under the net actions of electrostatic, gravitational, neutral collisional, and Lorentz forces. But the dust particles will not locate in the plasma sheath if their radius is beyond a certain value.
文摘Our experiment shows that the dust grains, suspended on the edge of the sheath of a radio-frequency discharge, undergo a contraction when switching a vertical magnetic field on, and an expansion when switching the magnetic field off. We call this kind of magnetic field "transient magnetic field". A primary analysis is proposed for the phenomenon.
基金supported in part by the JSPS-CAS Core-University Program in the field of Plasma and Nuclear Fusion
文摘Induced charge of a spherical dust particle on a plasma-facing wall was investigated analytically, where non-uniform electric field was applied externally. The one-dimensional nonuniform electrostatic potential was approximated by the polynomial of the normal coordinate toward the wall. The bipolar coordinate was introduced to solve the Laplace equation of the induced electrostatic potential. The boundary condition at the dust surface determines the unknown coefficients of the general solution of the Laplace equation for the induced potential. From the obtained potential the surface induced charge can be calculated. This result allows estimating the effect of the surrounding plasma, which shields the induced charge.
