Opportunities and limitations for ion beams in radiation effects studies: Bridging critical gaps between charged particle and neutron irradiations

Ion beams are indispensible for understanding radiation effects in materials, enabling access to conditions challenging to perform with neutrons. However, ion irradiations can produce potential artifacts from beam rastering, high displacement damage rate effective “temperature shifts”, subthreshold collisions, high ionization rates, and non-monoenergetic primary knock-on atom energies. The influence of near-surface denuded zones and implanted ion effects is analyzed, including diffusional broadening effects. At high ion irradiation energies, “swift heavy ion” effects can lead to enhanced defect production or recovery. Ion energies of 10–50 MeV typically offer a good compromise for minimizing near-surface, implanted ion, and swift heavy ion effects.