Influence of the Ion Beam on the Behavior of Dust Particles Trapped in an Ion Sheath

Influence of the ion beam on the levitation position of a dust particle trapped in an ion sheath has been investigated in a simple calculation and experiment by using a double plasma device. In the numerical analysis, when the ion beam density is relatively small, the levitated height of the dust particle is found to decrease with an increase in the ion beam density until the ion drag force becomes as large as the gravity force, because the existence of the ion beam component in the ion sheath modifies the potential profile and the charge of a dust particle. The experimental observation in the double plasma device agrees with this calculation results