Temporal single-surface multipactor dynamics under obliquely incident linearly polarized electric field

It is well-known that single-surface multipactor discharges can negatively affect electromagnetic wave transmission, especially in high power microwave devices and space-based communication systems. In this work, the temporal single-surface multipactor dynamics under an obliquely incident linearly polarized electric field are investigated by particle-in-cell simulations. The results reveal that multipactor discharges highly decay by adjusting the angle, theta, between the rf electric field and the dielectric window. For plane waves with theta = 0, the number of electrons as a function of time oscillates at twice the rf frequency. However, alternative oscillations decrease in magnitude at theta=0.05 pi and disappear at theta=0.15 pi. This is because the perpendicular component of the rf electric field alternatively reinforces or reduces the restoring field and increases or decreases the secondary electron emission in half of the rf period. In addition, the electrons are forced into a few branches in the phase space of velocity and position, i.e., the electrons have a few groups of velocities at a fixed position due to the largely increased electron flight time. Finally, multipactor suppression is investigated by a simple kinetic model, by which the susceptibility diagram is obtained. This diagram shows the upper and lower boundaries gradually approach each other upon increasing theta from 0 to 0.2 pi, indicating reduced parameter space, in which multipactor discharge can develop. Published under license by AIP Publishing.