Molecular dynamics simulation of radiation damage cascades in diamond

Buchan, JT; Robinson, M; Christie, HJ; Roach, D; Ross, DK; Marks, NA

Abstract

Radiation damage cascades in diamond are studied by molecular dynamics simulations employing the Environment Dependent Interaction Potential for carbon. Primary knock-on atom (PKA) energies up to 2.5 keV are considered and a uniformly distributed set of 25 initial PKA directions provide robust statistics. The simulations reveal the atomistic origins of radiation-resistance in diamond and
provide a comprehensive computational analysis of cascade evolution and dynamics. As for the case of graphite, the atomic trajectories are found to have a fractal-like character, thermal spikes are absent and only isolated point defects are generated. Quantitative analysis shows that the instantaneous maximum kinetic energy decays exponentially with time, and that the timescale of the ballistic phase has a power-law dependence on PKA energy. Defect recombination is efficient and independent of PKA energy, with only 50% of displacements resulting in defects, superior to graphite where the same quantity is nearly 75%.

Citation

Buchan, J., Robinson, M., Christie, H., Roach, D., Ross, D., & Marks, N. (2015). Molecular dynamics simulation of radiation damage cascades in diamond. Journal of Applied Physics, 117(24), https://doi.org/10.1063/1.4922457

• Journal Article Type: Article
• Acceptance Date: May 26, 2015
• Publication Date: Jun 28, 2015
• Deposit Date: Jul 10, 2015
• Publicly Available Date: Apr 5, 2016
• Journal: Journal of Applied Physics
• Print ISSN: 0021-8979
• Electronic ISSN: 1089-7550
• Publisher: AIP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 117
• Issue: 24
• DOI: https://doi.org/10.1063/1.4922457
• Publisher URL: http://dx.doi.org/10.1063/1.4922457
• Related Public URLs: http://scitation.aip.org/content/aip/journal/jap;jsessionid=29wa25sciqai8.x-aip-live-06
• Additional Information: Access Information : Data used in this research can be accessed via https://doi.org/10.17866/rd.salford.c.4864299.v1; Funders : Australian Government;Government of Western Australia;Australian Research Council; Grant Number: FT120100924