Publication Date:
2016-12-09
Description:
Microwave linear plasmas sustained by surface waves have attracted much attention due to the potential abilities to generate large-scale and uniform non-equilibrium plasmas. An external magnetic field was generally applied to enhance and stabilize plasma sources because the magnetic field decreased the electron losses on the wall. The effects of magnetic field on the generation and propagation mechanisms of the microwave plasma were tentatively investigated based on a 2-D numerical model combining a coupled system of Maxwell's equations and continuity equations. The mobility of electrons and effective electric conductivity of the plasma were considered as a full tensor in the presence of magnetic field. Numerical results indicate that both cases of magnetic field in the axial-direction and radial-direction benefit the generation of a high-density plasma; the former one allows the microwave to propagate longer in the axis direction compared to the latter one. The time-averaged power flow density and the amplitude of the electric field on the inner rod of coaxial waveguide attenuate with the propagation of the microwave for both cases of with and without external magnetic field. The attenuation becomes smaller in the presence of appropriately higher axial-direction magnetic field, which allows more microwave energies to transmit along the axial direction. Meanwhile, the anisotropic properties of the plasma, like electron mobility, in the presence of the magnetic field confine more charged particles in the direction of the magnetic field line.
Print ISSN:
1070-664X
Electronic ISSN:
1089-7674
Topics:
Physics
