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Nanowire Gold Chains: Formation Mechanisms and Conductance

H. Hakkinen·R. N. Barnett·A. G. Scherbakov·U. Landman
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Abstract

Structural transformations, electronic spectra and ballistic transport in pulled gold nanowires are investigated with ab initio simulations, and correlated with recent measurements. Strain-induced yield of an initial double-strand wire results first in formation of a bent-chain which transforms upon further elongation to a linear atomic chain exhibiting dimerized atomic configurations. These structures are stabilized by directional local bonding with spd-hybridization. The conductance of the initial double-stranded contact is close to 2g_0 and it drops sharply to 1g_0 during the transformation to a single chain, exhibiting subsequently a 1g_0 plateau extending over an elongation well above typical Au-Au distances.

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H. Hakkinen, R. N. Barnett, A. G. Scherbakov, U. Landman. 2000-09-11. Nanowire Gold Chains: Formation Mechanisms and Conductance. https://arxiv.org/abs/cond-mat/0009154

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