JefiPIC: A 3-D Full Electromagnetic Particle-in-Cell Simulator Based on Jefimenko's Equations on GPU

In this paper, we have proposed a new 3-D particle-in-cell (PIC) code which employs the integral Jefimenko's equations as the electromagnetic field solver. The challenging task is made possible with the help of the state-of-the-art graphic processing units (GPU) apparatus. To match the location of the fields and current densities defined in Jefimenko's equations, we have modified the field and charge interpolation methods. Different from the classical finite-difference time-domain (FDTD) method, the integral equations do not require strict charge conservation approaches during the particle emission moments. Our proposed method can naturally deal with the electrostatic problem, and does not need to deal with the boundary conditions, which is appropriate in solving open boundary plasma systems. To verify our code, we compare the particle evolution of a pure electron system simulated by two other codes: one is an open-source 3-Dimensional (3-D) PIC code based on FDTD, and the other is a 3-D numerical Boltzmann equations solver using Jefimenko's equations. The numerical results imply that it is beneficial to combine the time consuming Jefimenko's equations and the PIC method to provide accurate electromagnetic fields and particle distributions in describing open-boundary plasma systems. Our verification demonstrates that we can accomplish such task within an acceptable execution time with the use of the GPU.