Comparative analysis of dielectric surface discharge characteristics in Gaussian and sinusoidal microwave electric fields

Abstract

The particle-in-cell-Monte Carlo collision model is used to simulate the dielectric surface discharge in Gaussian and sinusoidal microwave electric fields. The effect of microwave electric field waveform on the discharge characteristics in vacuum and gases of different pressures is investigated, when the transmission power of Gaussian microwave is equal to that of sinusoidal microwave. In vacuum, the growth rate and saturation level of the number of electrons produced by multipactor in the Gaussian microwave electric field are lower than those in the sinusoidal microwave electric field. This is attributed to the lower amplitude of the mean electron energy in the Gaussian microwave electric field. At low pressure, the growth rate of the number of electrons generated by multipactor and gas ionization in the Gaussian microwave electric field is also lower than that in the sinusoidal microwave electric field. However, the plasma grows more rapidly in the Gaussian microwave electric field than in the sinusoidal microwave electric field at high pressure. This is because the rate of gas ionization that dominates the dielectric surface discharge in the Gaussian microwave field is higher than that in the sinusoidal microwave field.