Effects of irradiation-induced electronic excitation on simple and complex oxides

摘要

Nuclear materials are commonly subjected toirradiation by energetic particles. The transfer of energyfrom these particles to materials, known as particlestopping, falls into one of two distinct regimes. Nuclearstopping, which occurs for particles of low specific energy,involves elastic collisions with atomic nuclei that leaddirectly to atomic displacement. This commonly-studiedregime is typical of neutron irradiation experienced bynuclear materials. At higher particle specific energieselectronic stopping dominates. This entails inelasticinteractions of the particle with electrons in the irradiatedmaterial, exciting them and yielding a warm dense matterstate wherein a hit electron-hole plasma coexists withrelatively cool atomic nuclei. Subsequent electronicrelaxation yields complex atomic rearrangements,sometimes inducing unique and unexpected phasetransitions. The effects of irradiation in the electronicstopping regime on materials are summarized in Fig. 1.