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Sample-specific and Ensemble-averaged Magnetoconductance of Individual Single-Wall Carbon Nanotubes

H. T. Man·A. F. Morpurgo
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Abstract

We discuss magnetotransport measurements on individual single-wall carbon nanotubes with low contact resistance, performed as a function of temperature and gate voltage. We find that the application of a magnetic field perpendicular to the tube axis results in a large magnetoconductance of the order of e^2/h at low temperature. We demonstrate that this magnetoconductance consists of a sample-specific and of an ensemble-averaged contribution, both of which decrease with increasing temperature. The observed behavior resembles very closely the behavior of more conventional multi-channel mesoscopic wires, exhibiting universal conductance fluctuations and weak localization. A theoretical analysis of our experiments will enable to reach a deeper understanding of phase-coherent one-dimensional electronic motion in SWNTs.

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H. T. Man, A. F. Morpurgo. 2005-07-28. Sample-specific and Ensemble-averaged Magnetoconductance of Individual Single-Wall Carbon Nanotubes. https://doi.org/10.1103/physrevlett.95.026801

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