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arXiv · 1002.0719

Deformation Potentials and Electron-Phonon Coupling in Silicon Nanowires

F. Murphy-Armando·G. Fagas·J. C. Greer
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Abstract

The role of reduced dimensionality and of the surface on electron-phonon (e-ph) coupling in silicon nanowires is determined from first principles. Surface termination and chemistry is found to have a relatively small influence, whereas reduced dimensionality fundamentally alters the behavior of deformation potentials. As a consequence, electron coupling to "breathing modes" emerges that cannot be described by conventional treatments of e-ph coupling. The consequences for physical properties such as scattering lengths and mobilities are significant: the mobilities for [110] grown wires are 6 times larger than those for [100] wires, an effect that cannot be predicted without the form we find for Si nanowire deformation potentials.

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F. Murphy-Armando, G. Fagas, J. C. Greer. 2010-02-03. Deformation Potentials and Electron-Phonon Coupling in Silicon Nanowires. https://doi.org/10.1021/nl9034384

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