Lattice Boltzmann Simulations for Melting and Resolidification of Ultrashort Laser Interaction with Thin Gold Film

Abstract

The interaction between the laser and material is commonly described by the macroscale method, two-temperature model (TTM), and the microscale method, molecular dynamics. In the present paper, the melting and resolidification of ultrashort laser interaction with thin gold film is investigated in terms of a meso-scale method. The lattice Boltzmann method (LBM) including the electron–phonon collision term is established. A fixed grid approach is applied in the phonon subsystem to describe the phase change. The transition zone between solid and liquid is treated as the porous medium. The results predicted by the LBM coincide with the experiment data quite well. In addition, the detailed comparisons between the TTM with interfacial tracking method and the LBM are conducted. The influences of the laser fluences and pulse widths on the transition phase are also investigated.