Electron extraction enhancement via the magnetic field in a miniature microwave discharge neutralizer

Abstract

This study analyzes the dependence of electron extraction efficiency, which is defined as the ratio of the extracted electron current to the generated electron current, on the

Electron loss mechanisms in a miniature microwave discharge water neutralizer

“…shown in the figure, each density has reached a quasi-steady state, although there are some periodic oscillations attributed to plasma instability, as shown in our previous papers, 15,18,19 which has been frequently observed in other E × B devices. Figure 4 shows the classification of the neutralizer walls and time-averaged fractions of the electron currents at each boundary, where the electron current toward the sidewall is not presented because it was negligibly small (less than 0.1%).…”

“…MF-1 is the conventional magnetic field, and MF-2 is the optimized magnetic field, where the performance of the xenon neutralizer was improved in the previous study. 15 Here, the neutralizer performance was evaluated by the electron extraction efficiency, which is defined as the ratio of the extracted electron current to the generated electron current.…”

“…Here, we employed the real electron to ion mass ratio without introducing an artificial mass ratio to capture the physics of electron motion. In a previous study, 15 3D particle simulations revealed that the electron extraction efficiency, which is defined as the ratio of the extracted electron current to the generated electron current, achieved a 1.5-times higher value in an optimized magnetic field configuration, where the magnetic field lines passed through…”

“…based on our previous papers. [15][16][17][18][19] First, we set the initial conditions; then, we solved Maxwell's equations using the FDTD algorithm for the electromagnetic fields of the microwaves to obtain a steady-state solution without plasma. Second, we conducted electrostatic PIC-MCC simulations using the time-varying electric field of microwaves calculated by the FDTD algorithm, the electrostatic electric field of plasma, and the magnetic fields produced by permanent magnets.…”

“…In the previous study, the electron extraction efficiency of the xenon neutralizer with MF-2 was increased by 1.5 times. 15 Hence, in this study, we also conducted simulations for the water neutralizer with MF-1 and MF-2 and compared the electron extraction efficiency. This is the author's peer reviewed, accepted manuscript.…”