Molecular dynamics simulation of latent track formation in α-quartz

Abstract

The latent ion track in α-quartz is studied by molecular dynamics simulations. The latent track is created by depositing electron energies into a cylindrical region with a radius of 3 nm. In this study, the electron stopping power varies from 3.0 keV/nm to 12.0 keV/nm, and a continuous latent track is observed for all the simulated values of electron stopping power except 3.0 keV/nm. The simulation results indicate that the threshold electron stopping power for a continous latent track lies between 3.0 keV/nm and 3.7 keV/nm. In addition, the coordination defects produced in the latent track are analyzed for all the simulation conditions, and the results show that the latent track in α-quartz consists of an O-rich amorphous phase and Si-rich point defects. At the end of this paper, the influence of the energy deposition model on the latent track in α-quartz is investigated. The results indicate that different energy deposition models reveal similar latent track properties. However, the values of the threshold electron stopping power and the ion track radius are dependent on the choice of energy deposition model.