Lorentz boosted frame simulation of Laser wakefield acceleration in quasi-3D geometry

Abstract

When modeling laser wakefield acceleration (LWFA) using the particle-in-cell (PIC) algorithm in a Lorentz boosted frame, the plasma is drifting relativistically at ${\beta }_{b}c$ towards the laser, which can lead to a computational speedup of $\sim {\gamma }_b^2=(1-{\beta }_b^2{)}^{-1}$. Meanwhile, when LWFA is modeled in the quasi-3D geometry in which the electromagnetic fields and current are decomposed into a limited number of azimuthal harmonics, speedups are achieved by modeling three dimensional problems with the computation load on the order of two dimensional $r-z$ simulations. Here, we describe how to combine the speed ups from the Lorentz boosted frame and quasi-3D algorithms. The key to the combination is the use of a hybrid Yee-FFT solver in the quasi-3D geometry that can be used to effectively eliminate the Numerical Cerenkov Instability (NCI) that inevitably arises in a Lorentz boosted frame due to the unphysical coupling of Langmuir modes and EM modes of the relativistically drifting plasma in these simulations. In addition, based on the space-time distribution of the LWFA data in the lab and boosted frame, we propose to use a moving window to follow the drifting plasma to further reduce the computational load. We describe the details of how the NCI is eliminated for the quasi-3D geometry, the setups for simulations which combine the Lorentz boosted frame and quasi-3D geometry, the use of a moving window, and compare the results from these simulations against their corresponding lab frame cases. Good agreement is obtained, particularly when there is no self-trapping, which demonstrates it is possible to combine the Lorentz boosted frame and the quasi-3D algorithms when modeling LWFA to achieve unprecedented speedups.

References in corpus (7)

• Generating multi-GeV electron bunches using single stage laser wakefield acceleration in a 3D nonlinear regime
• Implementation of a hybrid particle code with a PIC description in r-z and a gridless description in $\varphi$ into OSIRIS
• Suppressing the Numerical Cherenkov Instability in FDTD PIC Codes
• Numerical stability analysis of the Pseudo-Spectral Analytical Time-Domain PIC algorithm
• Elimination of the numerical Cerenkov instability for spectral EM-PIC codes
• Modeling of Laser wakefield acceleration in Lorentz boosted frame using EM-PIC code with spectral solver
• Mitigation of numerical Cerenkov radiation and instability using a hybrid finite difference-FFT Maxwell solver and a local charge conserving current deposit

Cited by in corpus (7)

• A quasi-static particle-in-cell algorithm based on an azimuthal Fourier decomposition for highly efficient simulations of plasma-based acceleration: QPAD
• On numerical errors to the fields surrounding a relativistically moving particle in PIC codes
• On the generation of ultra-bright and low energy spread electron beams in laser wakefield acceleration in a uniform plasma
• Integrating a ponderomotive guiding center algorithm into a quasi-static particle-in-cell code based on azimuthal mode decomposition
• Convergence in nonlinear laser wakefield accelerators modeling in a Lorentz-boosted frame
• Combined tools for Particle-In-Cell simulations performed with transversely asymmetric chirped lasers
• Optimized matching conditions for self-guided laser wakefield accelerators