Abstract

The gridless Particle-In-Fourier method where particles are directly deposited onto a Fourier basis features excellent energy and momentum conservation properties, but is computationally expensive due to the global nature of its basis functions. In this paper, we investigate analytically and numerically how well a back-filtered spectral Particle-In-Cell method can approximate the Particle-In-Fourier method. The study is extended to a recent variational spectral PIC method which has a discrete Hamiltonian structure.