Nonlinear dynamics of slow ions near the cyclotron resonance: A possibility for optimization of an electrodeless plasma thruster
Phys. Rev. E 113, 065203 – Published 3 June, 2026
DOI: https://doi.org/10.1103/lrt3-n67h
Abstract
The cyclotron resonance dynamics of ions in a uniform magnetic field under the action of a plane left-handed polarized wave is considered. The dynamics of initially slow ions is nonlinear: they periodically synchronously (regardless of the initial phase of interaction) gain and then lose energy. The maximum acquired energy and the duration of such cycles depend, in particular, on the magnitude of the shift of the magnetic field in the interaction region relative to the resonant value (determined by the frequency of the wave) and the longitudinal wave number of the wave. The latter, in the case where the wave is an eigenmode, also depends on the magnitude of the shift. The possibility of optimizing the ion-cyclotron heating unit of VASIMR-type thrusters lies in determining the parameters of its magnetic configuration, at which the increase in the energy of ions during their flight through the resonant interaction zone is maximum. It is shown that the optimal value of the magnetic field in the interaction zone is approximately 0.5% higher than the resonant one, and a compact expression is obtained for the optimal length of the zone with a given field value.
