The microscopic model of material excitation in swift heavy ion tracks

The paper presents a quantitative model describing the kinetics of the electronic and ionic subsystems of a target along the trajectory of a swift heavy ion (SHI) decelerated in the electronic stopping regime. Electron-to-lattice energy and momentum transfer is described within the dynamic structure factor (DSF) formalism which takes into account different extreme cases of dynamic correlations in the ionic system of a target in a relaxing SHI track. The DSF approach gives an ability to merge Monte-Carlo and Molecular-Dynamics approaches simulating the kinetics of the electron ensemble and the lattice, respectively, into a unified model. This hybrid model predicts a little heating of the lattice in SHI tracks in LiF crystals that agrees well with the experiment-based estimation of this heating. The developed tool can be used for modeling of the kinetics of highly exited material states in swift heavy ion tracks and/or laser spots. (copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)