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arXiv · 0804.3219

Charge pumping in carbon nanotube quantum dots

M. R. Buitelaar·V. Kashcheyevs·P. J. Leek·V. I. Talyanskii·C. G. Smith·D. Anderson·G. A. C. Jones·J. Wei·D. H. Cobden
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Abstract

We investigate charge pumping in carbon nanotube quantum dots driven by the electric field of a surface acoustic wave. We find that at small driving amplitudes, the pumped current reverses polarity as the conductance is tuned through a Coulomb blockade peak using a gate electrode. We study the behavior as a function of wave amplitude, frequency and direction and develop a model in which our results can be understood as resulting from adiabatic charge redistribution between the leads and quantum dots on the nanotube.

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M. R. Buitelaar, V. Kashcheyevs, P. J. Leek, V. I. Talyanskii, C. G. Smith, D. Anderson, G. A. C. Jones, J. Wei, D. H. Cobden. 2008-04-20. Charge pumping in carbon nanotube quantum dots. https://doi.org/10.1103/physrevlett.101.126803

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