Suppression of Multipactor Discharge by Using Graphene Coating of the Inner Walls of the Microwave Cavity

The paper presents the results of the experimental study of the effect of coating the inner walls of the microwave resonator with graphene on its electrodynamic parameters and the temporal evolution of the secondary emission resonant discharge (multifactor effect). Resonator of toroidal type with a resonance frequency of 2459 MHz was used. The gap distance between the electrode was 4 mm. Excitation of the resonator was carried out by a microwave generator with a maximum pulse microwave power up to 100 W and pulse duration 6 $\mu$s. In this work we investigate the development of the multipactor on the copper electrodes, the surface of which was coated with graphene by chemical vapor deposition method. It is shown that the graphene coating does not affect the electrodynamic parameters of the resonator (such as resonant frequency and quality factor) and suppresses the multipactor discharge in the used geometry of the cavity and the investigated range of microwave power.