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arXiv · 0704.3451

Localized Electron States Near a Metal-Semiconductor Nanocontact

Denis O. Demchenko·Lin-Wang Wang
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Abstract

The electronic structure of nanowires in contact with metallic electrodes of experimentally relevant sizes is calculated by incorporating the electrostatic polarization potential into the atomistic single particle Schrödinger equation. We show that the presence of an electrode produces localized electron/hole states near the electrode, a phenomenon only exhibited in nanostructures and overlooked in the past. This phenomenon will have profound implications on electron transport in such nanosystems. We calculate several electrode/nanowire geometries, with varying contact depths and nanowire radii. We demonstrate the change in the band gap of up to 0.5 eV in 3 nm diameter CdSe nanowires and calculate the magnitude of the applied electric field necessary to overcome the localization.

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Denis O. Demchenko, Lin-Wang Wang. 2007-04-25. Localized Electron States Near a Metal-Semiconductor Nanocontact. https://doi.org/10.1021/nl072027n

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