Asymmetric PML for the absorption of waves. Application to mesh refinement in electromagnetic Particle-In-Cell plasma simulations

We present an extension of the Bérenger Perfectly Matched Layer with additional terms and tunable coefficients which introduce some asymmetry in the absorption rate. We show that the discretized version of the new PML offers superior absorption rates than the discretized standard PML under a plane wave analysis. We also introduce a new method for applying the Mesh Refinement technique to electromagnetic Particle-In-Cell plasma simulations which takes advantage of the high rates of absorption of the new PML. We present the details of the algorithm as well as a 2D example of its application to laser–plasma interaction in the context of fast ignition.