Ion Track Formation via Electric-Field-Enhanced Energy Deposition

TL;DR

This paper presents a novel electric-field-assisted method to enhance energy deposition during ion irradiation, enabling better control of ion track formation in materials like amorphous SiO2, with implications for material modification and nanoengineering.

Contribution

It introduces an electric-field-enhanced energy deposition technique during ion irradiation and extends the thermal spike model to predict its effects, overcoming intrinsic velocity limits.

Findings

Enhanced energy deposition reduces the threshold for ion track formation.

Model predictions align well with experimental data.

Method broadens applications in material modification and nanoengineering.

Abstract

High-energy ion irradiation deposits extreme energy in a narrow range (1-10 nm) along ion trajectories in solid through electronic energy loss, producing unique irradiation effects such as ion tracks. However, intrinsic velocity effects impose an upper limit on electronic energy loss that cannot be overcome by adjusting irradiation parameters. We introduce a method using electric fields during irradiation to enhance nanoscale energy deposition by accelerating ion-excited electrons within sub-picosecond timescales.Our extended thermal spike model quantitatively describes this enhancement and predicts a significant reduction in the electronic energy loss required for ion track formation in amorphous SiO2, which is in excellent agreement with experimental observations. This work provides a new approach to control energy deposition during irradiation and boosts the wide application of ion tracks in material modification and nanoengineering to much broader extents.