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arXiv · 1006.5872

Optical Phonon Lineshapes and Transport in Metallic Carbon Nanotubes under High Bias Voltage

Juergen Dietel·Hagen Kleinert
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Abstract

We calculate the current-voltage characteristic of metallic nanotubes at high bias voltage showing that a bottleneck exists for short nanotubes in contrast to large ones. We attribute this to a redistribution of lower-lying acoustic phonons caused by phonon-phonon scattering with hot optical phonons. The current-voltage characteristic and the electron and phonon distribution functions are derived analytically, and serve to obtain in a self-contained way the frequency shift and line broadening of the zone center optical phonons due to the electron-phonon coupling at high bias. We obtain a positive frequency shift from the zero bias shift and no broadening of the optical phonon mode at very high voltages, in agreement with recent experiments.

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Juergen Dietel, Hagen Kleinert. 2010-12-07. Optical Phonon Lineshapes and Transport in Metallic Carbon Nanotubes under High Bias Voltage. https://doi.org/10.1103/physrevb.82.195437

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