Ab initio molecular dynamics calculations of threshold displacement energies in silicon carbide

TL;DR

This study uses ab initio molecular dynamics to accurately calculate threshold displacement energies and defect formation in silicon carbide, aligning well with experimental data and advancing first principles methods for covalent materials.

Contribution

It demonstrates the feasibility of first principles calculations for displacement energies in silicon carbide, improving accuracy over classical methods and providing insights into defect stability.

Findings

Threshold displacement energies close to experimental values

Created defects consistent with recent defect stability studies

First principles approach is viable for covalent materials

Abstract

Using first principles molecular dynamics simulations, we have determined the threshold displacement energies and the associated created defects in cubic silicon carbide. Contrary to previous studies using classical molecular dynamics, we found values close to the experimental consensus, and also created defects in good agreement with recent works on interstitials stability in silicon carbide. We carefully investigated the limits of this approach. Our work shows that it is possible to calculate displacement energies with first principles accuracy in silicon carbide, and suggests that it may be also the case for other covalent materials.