Femtosecond studies of highly excited electrons in metals

Time-resolved measurement of electron temperature was performed through femtosecond studies of highly excited electrons in aluminum alloy, and the process of electron–lattice energy transfer was measured to be 1–3 ps, increasing with the laser fluence. Two ablation regimes were found in the logarithmic dependence of the ablated depth on laser fluence, and two components were attributed to the optical and energy penetration. The surface micrographs of the scanning electron microscopy (SEM) were characterized as a function of incident laser fluence. The surface features ranging from submicron to microns were developed through the variation in laser fluence and count of laser pulse.