Parametric aspects of electron–phonon temperature model for short pulse laser interactions with thin metallic films

Abstract

This work studies one-dimensional and two-dimensional heat transfer for short pulse lasers (<1 ps in duration) applied on metals using a two-subsystem (i.e., electrons and phonons) temperature model. In this model laser energy is first deposited on the electrons, which then exchange energy with the lattice. Conduction of energy is by electron motion only and the lattice contributes to the scattering of electrons. The objectives of this study are (a) to analyze the effects of different parameters such as electron specific heat, lattice specific heat, electron–phonon coupling factor, and thermal relaxation time for the one-dimensional electron and lattice temperature distributions using both hyperbolic and Fourier heat conduction formulations; (b) to examine two-dimensional effects including the effects of laser beam radial variance, laser fluence, and laser power in addition to the above parameters; and (c) to solve the transient equation of radiative transfer to incorporate the wave nature of the radiative source for the one-dimensional case.