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arXiv · 0901.2947

Direct Observation of Born-Oppenheimer Approximation Breakdown in Carbon Nanotubes

Adam W. Bushmaker·Vikram V. Deshpande·Scott Hsieh·Marc W. Bockrath·Stephen B. Cronin
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Abstract

Raman spectra and electrical conductance of individual, pristine, suspended, metallic single-walled carbon nanotubes are measured under applied gate potentials. The G- band is observed to downshift with small applied gate voltages, with the minima occurring at EF = +/- 1/2 Ephonon, contrary to adiabatic predictions. A subsequent upshift in the Raman frequency at higher gate voltages results in a 'W'-shaped Raman shift profile that agrees well with a non-adiabatic phonon renormalization model. This behavior constitutes the first experimental confirmation of the theoretically predicted breakdown of the Born-Oppenheimer approximation in individual single walled carbon nanotubes.

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Adam W. Bushmaker, Vikram V. Deshpande, Scott Hsieh, Marc W. Bockrath, Stephen B. Cronin. 2009-01-19. Direct Observation of Born-Oppenheimer Approximation Breakdown in Carbon Nanotubes. https://doi.org/10.1021/nl802854x

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