Evolution from the gradient drift instability to the formation of the spoke potential hump in a partially magnetized plasma

Rotating spokes commonly occur in partially magnetized plasma devices. This work explores the evolution from gradient drift instability into an m = 1 rotating spoke mode a magnetically enhanced hollow cathode discharge (with emissive cathode) by means of 2D radial-azimuthal particle-in-cell/Monte Carlo collision simulations. It is shown that formation potential hump region can be explained as result local collapse anode sheath due to instability, which triggered within sheath. The non-neutrality effect on considered and incorporated two-fluid linear theory instability. unstable modes predicted are good agreement with fluctuation developed particle