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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.

We use the two-temperature model in molecular dynamic simulations of 150 keV Ni ion cascades in nickel and nickel-based alloys to investigate the effect of the energy exchange between the atomic and the electronic systems during the primary stages of radiation damage. We find that the electron-phonon interactions result in a smaller amount of defects and affect the cluster formation, resulting in smaller clusters. These results indicate that ignoring the local heating due to the electrons results in the overestimation of the amount of damage and the size of the defect clusters. A comparison of the average defect production to the Norgett-Robinson-Torrens (NRT) prediction over a range of energies is provided.

We use the inelastic thermal spike model for insulators and molecular dynamic simulations to investigate the effects of pre-existing damage on the energy dissipation and structural alterations in KTaO3 under irradiation with 21 MeV Ni ions. Our results reveal a synergy between the pre-existing defects and the electronic energy loss, indicating that the defects play an important role on the energy deposition in the system. Our findings highlight the need for better understanding on the role of defects in electronic energy dissipation and the coupling of the electronic and atomic subsystems.