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Discrete thinning dynamics in a continuum model of metallic nanowires

J. Bürki
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Abstract

Transmission electron microscopy experiments have recently observed gold metal nanocylinders to thin down in a discrete manner: A kink--a step of order of one atomic layer--nucleates at one end and then moves along the wire, leaving a thinner cylinder behind it. In this paper, I show that a similar thinning process takes place within the nanoscale free-electron model, a structural and dynamical model of nanowires that treats the electron-confinement effects exactly while replacing the atomic structure by a continuum. Electron-shell effects, previously shown to be responsible for the stability of wires with magic radii, favor the formation of kinks connecting magic cylinders. A rich kink dynamics including interkink interactions ensues and is similar to that observed experimentally.

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J. Bürki. 2007-04-17. Discrete thinning dynamics in a continuum model of metallic nanowires. https://doi.org/10.1103/physrevb.75.205435

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