Temporal laser source term from experimental data for laser-matter interaction simulations

Abstract

Simulations on the interaction between laser pulses and materials require information on material and laser properties. While details on material properties are extensively studied, the temporal profile of the laser source term is assumed to have a standard Gaussian waveform. However, spectral data of a laser pulse showed a low correspondence with Gaussian curve. Here, we propose a multi-termed Gaussian function to derive the temporal function of laser pulses. By increasing the number of terms of the Gaussian function, we improved the RMSE between the data and the fitted spectral profile. We perform an inverse Fourier transform in the fitted spectral function to obtain the temporal profile of the laser source term. We compare the conventional single-termed Gaussian profile with the multi-termed Gaussian fit by calculating the electron and lattice temperature of a copper film through the well-known two-temperature model simulations.