Fig. 1. 2D simulation domain.

Fig. 2. V_x–x phase space plots for 100 eV “filling” beam. Left: Current neutralized, case 1.1. Right: Density neutralized, case 1.2. Top: Ion phase space. Bottom: Electron phase space. t=1.8e–6 s.

Fig. 3. V_x–x phase space plots for 1000 eV “filling” beam. Left: Current neutralized, case 1.3. Right: Density neutralized, case 1.4. Top: Ion phase space. Bottom: Electron phase space. t=1.2e–6 s.

Fig. 4. (A) 3D simulation domain; (B) 3D potential τ=2.2E–7 s.

Fig. 5. (A) 3D V_x–x phase space for ions. τ=2.2E–7 s; (B) 3D V_x–x phase space for electrons. τ=2.2E–7 s.

Table 1. 2D simulation parameters and current-density comparison results

Table 2. 2D velocity ratio simulation parameters and results

Table 3. Steady state simulation parameters and results

“Warm” ions indicate the ions were mobile and allowed to develop from a cold beam. “Frozen” ions indicate particles were place in the problem by the code in a perfectly cold beam.

Table 4. Current coupling simulation parameters and results

“Warm” ions indicate the ions were mobile and started from the developed case 3.2. “Cold” ions indicate the ions were immobile, but started from the developed case 3.2. “Frozen” ions indicates particles were placed in the problem by the code in a cold beam. The right electrode size is in multiples of the left electrode.