Electromagnetic particle-in-cell simulations of Applied-<i>B</i> proton diodes

Abstract

Fully electromagnetic particle-in-cell simulations of Applied-B ion diodes have been performed using the magic code. These calculations indicate that Applied-B diodes can be nearly 100% efficient. Furthermore, the simulations exhibit an impedance relaxation phenomenon due to the buildup of electron space charge near the anode which causes a time-dependent enhancement of the ion emission above the Child–Langmuir value. This phenomenon may at least partially explain the rapidly decreasing impedance that has been observed in Applied-B ion diode experiments. The results of our numerical simulations will be compared to experimental data on Applied-B ion diodes and to analytic theories of their operation.