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Conductance Quantization and Electron Resonances in Sharp Tips and Atomic-Size Contacts

A. Levy Yeyati·A. Martín-Rodero·F. Flores
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Abstract

The electronic and transport properties of atomic-size contacts are analyzed theoretically using a self-consistent tight-binding model. Our results show that, for s-like metals, a sufficiently narrow contact exhibits well defined resonant states at the Fermi energy, spatially localized in the neck region. These states are robust with respect to disorder and provide a simple explanation for the observed tendency to conductance quantization. It is also shown that these properties disappear for a sufficiently large contact area. The possible relevance of this resonant states in scanning tunneling spectroscopy using sharp tips is briefly analized.

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A. Levy Yeyati, A. Martín-Rodero, F. Flores. 1997-08-21. Conductance Quantization and Electron Resonances in Sharp Tips and Atomic-Size Contacts. https://doi.org/10.1103/physrevb.56.10369

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