Ultrafast energy transfer in metals in a strongly nonequilibrium state induced by subterawatt femtosecond laser pulses

The temporal dynamics of the change in the thermally-induced induced reflection coefficient of polycrystalline gold, aluminum, and molybdenum at a wavelength of $800$ nm as a result of exposure to a femtosecond laser pulse (at a wavelength of $400$ nm) with an intensity of up to $0.2$ TW in the in the picosecond time range is studied using pump-probe optical scheme with phase-sensitive detection. New experimental data are obtained on the change in the reflection coefficient under strongly nonequilibrium conditions when the electron subsystem is heated to temperatures of $\sim10$ kK, which are relevant for the development of the experimental base for numerical simulation.