Kinetic trajectory simulation method for the multi-component magnetized plasma sheath

Abstract

Using kinetic theory, the magnetized plasma sheath characteristics with two species of positive ions has been investigated. This work is based on the assumption that the electrons and both ions have cut-off Maxwellian distribution at the sheath entrance. In order to couple the presheath-sheath interface parameters, the 1d3v kinetic coupling equations are used. The most fundamental kinetic Bohm’s condition has been derived for the plasma consisting of two singly charged positive ions. It is found that the presence of a second ion species affects the amplitude of velocity distribution functions of both ion species at the sheath entrance as well as at the wall. The magnitude of cut-off and Maxwellian maximum velocities has same value at the sheath entrance whereas its value increases at the wall by increasing the concentration of the second ion species. Although ion and electron fluxes decrease towards the sheath region, both fluxes attain equal at the wall. In addition, it is shown that the self-consistent potential profile monotonically decreases towards the wall. The cut-off Maxwellian velocity distribution of electrons cause to deviate our simulation results from the theoretical results is less than 0.2% in magnitude.