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Very low shot noise in carbon nanotubes

P. -E. Roche·M. Kociak·S. Gueron·A. Kasumov·B. Reulet·H. Bouchiat
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Abstract

We have performed noise measurements on suspended ropes of single wall carbon nanotubes (SWNT) between 1 and 300 K for different values of dc current through the ropes. We find that the shot noise is suppressed by more than a factor 100 compared to the full shot noise 2eI. We have also measured an individual SWNT and found a level of noise which is smaller than the minimum expected. Another finding is the very low level of 1/f noise, which is significantly lower than previous observations. We propose two possible interpretations for this strong shot noise reduction: i) Transport within a rope takes place through a few nearly ballistic tubes within a rope and possibly involves non integer effective charges. ii) A substantial fraction of the tubes conduct with a strong reduction of effective charge (by more than a factor 50).

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P. -E. Roche, M. Kociak, S. Gueron, A. Kasumov, B. Reulet, H. Bouchiat. 2002-02-05. Very low shot noise in carbon nanotubes. https://doi.org/10.1140/epjb%2Fe2002-00223-9

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