The effect of electron–ion interactions on radiation damage simulations

Classical cascade simulations of radiation damage generally neglect the effect of energy exchange between the lattice and the electrons; however electronic effects increase with increasing radiation energy. Indeed, even for low energy radiation events the electrons contribute to heat transport and increase the cooling rate, particularly in materials with strong electron-ion interactions. We use a method described in an earlier publication to include these effects in a series of 10 keV cascades in Fe, for a range of electron-ion interaction strengths. We find a non-monotonic relationship between the number of residual defects and the strength of the electron-ion interactions and we discuss the mechanisms involved.