Upgrade of the IMD software tool for the simulation of laser-matter interaction

Abstract

The simulation of the laser ablation processes can be a valuable tool for studying coupling parameters and developing questions for future experiments. The theory behind the ablation process and the mathematical model to describe laser beam absorption are discussed. Further, the simulation tools IMD and Polly-2T, used at the Institute of Technical Physics, DLR Stuttgart, are introduced and a road map for the upgrade of IMD is proposed. This upgrade is aimed towards including a more advanced physics model present in Polly-2T into IMD, to enhance the validity of the laser absorption process for laser pulses beyond the femtosecond regime. This is achieved by implementing the target reflectivity according to the Fresnel formulas and dynamic calculation of the permittivity following a wide-range approximation of the permittivity for different material states. The wide-range approximation is also implemented for the electron thermal conductivity and the electron-phonon coupling. The implementation of critical upgrade steps in IMD is presented and the results are compared to Polly-2T. Persistent issues and bugs of the upgrade are discussed and possible solutions for future improvements and further upgrades are outlined.