Atomistic two-temperature modelling of ion track formation in silicon dioxide

¹ Helsinki Institute of Physics and Department of Physics, University of Helsinki - P.O. Box 43, FI-00014, Helsinki, Finland
² University College London, Department of Physics and Astronomy and London Centre for Nanotechnology Gower Street, London, WC1E 6BT, UK

Received: 13 October 2014
Accepted: 2 April 2015

Abstract

We study swift-heavy-ion track formation in α-quartz using the two-temperature molecular dynamics (2T-MD) model realised as a concurrent multiscale scheme. We compare the simulated track radii to the existing experimental ones obtained from small-angle X-ray scattering and Rutherford backscattering experiments. The 2T-MD model provides an explanation of the origin of the track radii saturation at high electronic stopping power. Furthermore, we study the track structure and show that defects formed outside the region of density fluctuations after a swift-heavy-ion impact may explain the conflicting track radii produced by the two experimental techniques.