Ultrafast electron-ion coupled dynamics of iron nano-foil in warm dense matter (WDM) conditions studies by time resolved XANES and ab-initio simulations

In recent years, significant progresses have been made in both ultrafast experimental measurements techniques as well as in computational modeling that allow us to access to fundamental properties such as electron-phonon coupling under electron-ion non-equilibrium conditions. In this presentation, we will discuss how a combination of time-resolved XANES experiment and ab-initio derived two-temperature model coupled with XANES simulation is used to study the spatiotemporal electron-ion relaxation behavior of nano-meter thin iron foil that is exposed to femto second laser pulse. We show that the current level of experimental time resolution is already sufficient to constraint thermophysical properties under non-equilibrium WDM conditions within a few tens of percent, however, for the optimal sensitivity, which depends strongly on the choices of geometrical design of target as well as corresponding laser fluece.