Transient optics of gold during laser irradiation: From first principles to experiment

Abstract

The reflectivity of noble metals can dramatically change upon ultrashort laser irradiation due to the heating of $d$ electrons to high temperatures. Knowledge of the resulting transient optics is fundamental for determining and controlling the absorbed energy. In this work, high-accuracy self-reflectivity measurements are performed and interpreted using a theory for the space-resolved and time-resolved energy absorption and dissipation. The combined approach yields the reflectivity of gold in dependence on the incident laser fluence for a wide spectral range.