Ultrashort laser pulse energy deposition in metal films with phase changes

Four optical models of reflectivity and absorption coefficient are investigated in this letter. After compared with existing experimental data, the extended Drude model is incorporated into a two-temperature model to simulate laser energy deposition and thermal response, including solid-liquid and liquid-vapor phase change, in a gold film irradiated by a femtosecond laser pulse. Dynamic reflectivity and absorption coefficient should be employed in modeling ultrafast laser heating except for very low laser fluencies.