Plasma confinement by highhyphen;power excitation in a waveguide

摘要

Under TE20mode excitation, the electric field in a rectangular waveguide is minimum at the center and has two intensity maxima at intermediate points. Consequently, the plasma electrons experience a strong ponderomotive force and are redistributed to assemble around intensity minima. A selfhyphen;consistent solution of the wave equation for this problem reveals that the plasma density around intensity minima may be enhanced by a factor of 10 for accessible rf power. It also suggests that the electromagnetic waves of frequency less than the plasma frequency ohgr;pcan penetrate a dense plasma. In a collisional plasma, the redistribution of electrons is predominantly caused by their inhomogeneous heating by the wave. The confinement in this case may be attained at much lower powers.