Electronic energy losses in radiation-induced collision cascades

Aktiviteetti: Kutsuttu akateeminen esitelmä

Description

The treatment of electronic effects in multi-million atom simulations of radiation induced collision cascades presents a long-standing challenge in the study of primary radiation damage formation. On the one hand, it is known that energetic projectiles lose energy through electronic stopping as they pass through a material. On the other hand, in near-equilibrium conditions, electrons and ions couple through the electron-phonon interaction. During collision cascades, atoms undergo a continuous transition from the high-energy regime to the equilibrium regime, while at the same time experiencing a highly disordered, under-dense state, surrounded by a higher pressure region. Neither electronic stopping theory nor electron-phonon coupling is suitable for fully describing this whole process.

Real-time time-dependent density functional theory (rt-TDDFT) has proven successful in computing the electronic stopping power of both light and heavy ions in a range of materials, and also allows for determining the dependence of the energy dissipation on the local atomic and electronic environment of the projectile. In this talk, I will describe recent advances in modeling radiation damage formation, achieved by considering the coupling between the atomic and electronic systems as a function of the local electronic density, parametrized by rt-TDDFT calculations. This allows for accurately treating the energy dissipation during the full evolution of the highly non-equilibrium cascade process, from the early ballistic stage through to the relaxation and cooling phase.
Aikajakso7 jouluk. 2022
Tapahtuman otsikkoQuantum Dissipation by Swift Nuclei in Condensed Matter
Tapahtuman tyyppiWorkshop
SijaintiLausanne, SveitsiNäytä kartalla
Tunnustuksen arvoInternational