Fast Fourier Transform periodic interpolation method for superposition sums in a periodic unit cell

Fangzhou Ai, Vitaliy Lomakin

Abstract: Highlights•FFT-PIM can handle problems with 1D/2D/3D periodicities for static or dynamic problems with or without a phase shift.•The computational complexity of FFT-PIM is of O(N log N). FFT-PIM is fast and accurate and only leads to a minimal overhead compared to non-periodic problem approaches.•FFT-PIM works for Helmholtz and Coulomb kernels, suitable for a range of applications, e.g., electromagnetics, acoustics, and micromagnetics.