Swift heavy ion track formation in nanoporous Si: Wave packet molecular dynamics study

Abstract

In this article we study the process of silicon relaxation after swift heavy ion (SHI) irradiation using first-principles-based electron force field eFF. We show that early stages of so-called nonthermal melting take place in the nanometric viscinity of SHI trajectory in both bulk Si and Si nanolayer, but result in structural modifications only for the last one. Our results shed light on recent experimental evidence of significant reduction of threashold for SHI-induced damage creation in nanoporous Si.