Molecular dynamics simulations of the response of pre-damaged SrTiO3 and KTaO3 to fast heavy ions

Abstract

We investigate the energy dissipation and track formation due to ion irradiation in SrTiO3 and KTaO3. We use molecular dynamics simulations combined with the inelastic thermal spike model to simulate 21 MeV Ni ion irradiation in pristine and predamaged samples. The results are validated against experimental findings, showing that the level of initial disorder affects the electron-phonon interactions and the energy dissipation and deposition to the atoms. It is predicted that the ion track size increases linearly for low disorder levels, while its size saturates for high levels of disorder.