Finite spatial-grid effects in energy-conserving particle-in-cell algorithms

Finite-grid (or aliasing) instabilities are pervasive in particle-in-cell (PIC) plasma simulation algorithms, and force the modeler to resolve smallest (Debye) length scale problem regardless of dynamical relevance. These originate aliasing interpolation errors between mesh quantities particles (which live space–time continuum). Recently, strictly energy-conserving PIC (EC-PIC) algorithms have been developed that promise enhanced robustness against instabilities. In this study, we confirm by analysis EC-PIC is stable for stationary plasmas. For drifting plasmas, demonstrate numerical experiments that, while not free from these principle, they feature a benign stability threshold finite-temperature plasmas make them usable practice large class problems (featuring ambipolarity realistic ion-electron mass ratios) without need consider size Debye length. We also absent popular momentum-conserving which therefore unstable both beyond cell compared