Ultrahigh-order Maxwell solver with extreme scalability for electromagnetic PIC simulations of plasmas

TL;DR

This paper introduces a novel ultrahigh-order Maxwell solver utilizing local FFTs, achieving extreme scalability and enabling accurate 3D plasma mirror simulations on supercomputers.

Contribution

A new local FFT-based method that provides ultrahigh-order accuracy with unprecedented scalability for electromagnetic PIC simulations.

Findings

Enables accurate 3D plasma mirror modeling.

Achieves ultrahigh-order accuracy with high scalability.

Surpasses limitations of traditional finite-difference methods.

Abstract

The advent of massively parallel supercomputers, with their distributed-memory technology using many processing units, has favored the development of highly-scalable local low-order solvers at the expense of harder-to-scale global very high-order spectral methods. Indeed, FFT-based methods, which were very popular on shared memory computers, have been largely replaced by finite-difference (FD) methods for the solution of many problems, including plasmas simulations with electromagnetic Particle-In-Cell methods. For some problems, such as the modeling of so-called "plasma mirrors" for the generation of high-energy particles and ultra-short radiations, we have shown that the inaccuracies of standard FD-based PIC methods prevent the modeling on present supercomputers at sufficient accuracy. We demonstrate here that a new method, based on the use of local FFTs, enables ultrahigh-order accuracy with unprecedented scalability, and thus for the first time the accurate modeling of plasma mirrors in 3D.