Title: Molecular dynamics simulations of breaking metallic nanowires

Authors: C. Guerrero, J.R. Villarroel, E. Medina, A. Hasmy, P.A. Serena

Addresses: Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas, Apartado 21827, Caracas 1020A, Venezuela. ' Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas, Apartado 21827, Caracas 1020A, Venezuela. ' Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas, Apartado 21827, Caracas 1020A, Venezuela. ' Centro de Fisica, Instituto Venezolano de Investigaciones Cientificas, Apartado 21827, Caracas 1020A, Venezuela. ' Instituto de Ciencias de Materiales de Madrid, Consejo Superior de Investigaciones Científicas, Cantoblanco, 28049-Madrid, Spain

Abstract: In the present work, we have reviewed the importance of conductance histograms as an experimental tool able to address the statistical behaviour of the electronic transport through metallic nanowires. We have described how molecular dynamics techniques combined with embedded-atom method (EAM) are able to reproduce the general features noticed during metallic nanowire breaking experiments. We have studied the effect of temperature on the minimum cross-section histograms. Our results show that the breaking dynamics is strongly temperature dependent, giving rise to remarkable changes in the computed histograms. We found, for Gold, that conductance and configuration histograms are not correlated, thus indicating that experimental conductance peaks are due to actual quantized conductance effects. For Aluminium, the situation is different, since we found a strong correspondence between our minimum cross-section histograms and the experimental conductance histograms, indicating the relevant role of atomic configurations. We have addressed the study of the stretching of thick Au and Al nanocontacts, finding that there is evidence of the formation of preferred atomic configurations. The electronic origin of such stable atomic arrangements has been discarded, and a plausible explanation has been given in terms of the completion of ionic shells or subshells. Gold and Aluminium nanowires present at room temperature a similar character to that found for alkali wires at low temperatures.

Keywords: metallic nanocontacts; metallic nanowires; conductance histograms; molecular dynamics; simulation; embedded atom method; EAM; nanotechnology.

DOI: 10.1504/IJNT.2004.004910

International Journal of Nanotechnology, 2004 Vol.1 No.3, pp.265 - 291

Published online: 19 Jul 2004 *

Full-text access for editors Access for subscribers Purchase this article Comment on this article