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.