Nonequilibrium electron energy distribution in Au under subpicosecond laser irradiation: A kinetic study

We have performed a kinetic study of the electron dynamic relaxation inside a Au
film subjected to a subpicosecond laser pulse. For this purpose, we have
developed a time-dependent numerical solution of the Boltzmann equation for the
electrons inside the film considering the collision integrals due to electron-electron
and electron-phonon collisions and a perturbation term due to the laser pulse. Our
results show that, after the pulse excitation, electron distributions are very far from
equilibrium. Therefore it is not possible, especially in the first part of the temporal
evolution, to describe the relaxation of the electron distribution through a
two-temperature model.