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arXiv · 0803.4426

Diameter-dependent conductance oscillations in carbon nanotubes upon torsion

K. S. Nagapriya·Savas Berber·Tzahi Cohen-Karni·Lior Segev·Onit Srur-Lavi·David Tomanek·Ernesto Joselevich
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Abstract

We combine electromechanical measurements with {\em ab initio} density functional calculations to settle the controversy about the origin of torsion-induced conductance oscillations in multi-wall carbon nanotubes. According to our observations, the oscillation period is inversely proportional to the squared diameter of the nanotube, as expected for a single-wall nanotube of the same diameter. This is supported by our theoretical finding that differential torsion effectively decouples the walls of a multi-wall nanotube near the Fermi level and moves the Fermi momentum across quantization lines. We exclude the alternative explanation linked to registry changes between the walls, since it would cause a different diameter dependence of the oscillation period.

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K. S. Nagapriya, Savas Berber, Tzahi Cohen-Karni, Lior Segev, Onit Srur-Lavi, David Tomanek, Ernesto Joselevich. 2008-03-31. Diameter-dependent conductance oscillations in carbon nanotubes upon torsion. https://arxiv.org/abs/0803.4426

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