Macroparticle rotation in the vacuum arc plasma jet

摘要

The motion of macroparticles (MPs) emitted from the cathode into the vacuum arc plasma jet is considered taking into account asymmetric ion bombardment of the MP surface. The MP velocity is increased up to 0.17 of the plasma jet velocity for an initial MP radius R_(0)=0.1 μm and up to 0.3 of the plasma jet velocity for R_(0)=0.02 μm. The electric current density distribution within the MP caused by the asymmetric plasma bombardment was calculated assuming homogeneous internal conductivity. The electric potential difference between the apex and antiapex points is ≈10~(-8) V for an MP radius of R_(0)=0.1 μm, while the average MP electric potential relative to the surrounding plasma is V≈-11.27 V. Interaction between the internal electric current and the magnetic field used to collimate the plasma jet rotates the MPs with a frequency of ≈10~(5) s~(-1).