Latent track formation and recrystallization in swift heavy ion irradiation

Abstract

Swift heavy ions (SHI) irradiation is a complex coupled multiphysics phenomenon with applications in studying the effects of fission fragments, nano-patterning, and material modification. However, existing models are oversimplified, e.g., inelastic thermal spike, or complicated with inherent size limitations, e.g., hybrid Monte Carlo molecular dynamic. Here, we present a phase-field inelastic thermal spike (PF-iTS) approach to predict the amorphization, recrystallization, and stress generation in a single-impact SHI scenario. Our model quantitatively predicts the latent track radius, which agrees with experiments. Also, the PF-iTS calculates superheating temperature, stress generation, and recrystallization that cannot be obtained with classical i-TS. The appearance of mean compressive stress at the center of the latent track explains the hillock and void formation in TiO₂, showing the importance of mechanical stresses in forming latent tracks during SHI irradiation.