Surface reconstruction in gold nanowires.

Surface reconstructions are caused by structural stabilization resulting from the modulation of surface atomic positions. Studies on surface reconstruction have been conducted for substantially large surfaces, rather than at the size of reconstructed surface unit cells. Hence, well-known surface reconstruction manners may not be applicable for the surfaces of nanometer-sized isolated crystals, such as nanoclusters, nanowires and nanotubes. This is because they have high surface area-to-interior volume ratios exceeding several tens of percent, and their surface structures significantly affect the stabilization of their entire structures. In this study, we demonstrate the inherent surface reconstruction of gold nanowires via nanosecond-pulsed electromigration with the application of tensile stresses. The results lead to evolutions in basic studies relating to surface reconstruction and nanostructures and in applications of nanowires, for which stabilization is essential when they are used in extremely miniaturized integrated circuits for next-generation electronics.