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Tunneling in suspended carbon nanotubes assisted by longitudinal phonons

S. Sapmaz·P. Jarillo-Herrero·Ya. M. Blanter·C. Dekker·H. S. J. van der Zant
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Abstract

Current-voltage characteristics of suspended single-wall carbon nanotube quantum dots show a series of steps equally spaced in voltage. The energy scale of this harmonic, low-energy excitation spectrum is consistent with that of the longitudinal low-k phonon mode (stretching mode) in the nanotube. Agreement is found with a Franck-Condon-based model in which the phonon-assisted tunneling process is modeled as a coupling of electronic levels to underdamped quantum harmonic oscillators. Comparison with this model indicates a rather strong electron-phonon coupling factor of order unity.

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S. Sapmaz, P. Jarillo-Herrero, Ya. M. Blanter, C. Dekker, H. S. J. van der Zant. 2005-08-10. Tunneling in suspended carbon nanotubes assisted by longitudinal phonons. https://doi.org/10.1103/physrevlett.96.026801

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