Thermal Wave Superposition and Reflection Phenomena During Femtosecond Laser Interaction with Thin Gold Film

Abstract

For the cases that the characteristic time is comparable to the relaxation time of the energy carriers, heat conduction can be interpreted as a form of wave propagation. In this article, the wave effects of both electron and lattice temperatures during interaction of two symmetric femtosecond laser beams with thin gold film are investigated using a dual hyperbolic two-step model. The results show an obvious overshoot phenomenon of thermal wave and oscillations of both electron and lattice temperatures. The influence of laser parameters on thermal wave propagation is also studied.