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arXiv · 1209.3735

Tunable Kondo physics in a carbon nanotube double quantum dot

S. J. Chorley·M. R. Galpin·F. W. Jayatilaka·C. G. Smith·D. E. Logan·M. R. Buitelaar
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Abstract

We investigate a tunable two-impurity Kondo system in a strongly correlated carbon nanotube double quantum dot, accessing the full range of charge regimes. In the regime where both dots contain an unpaired electron, the system approaches the two-impurity Kondo model. At zero magnetic field the interdot coupling disrupts the Kondo physics and a local singlet state arises, but we are able to tune the crossover to a Kondo screened phase by application of a magnetic field. All results show good agreement with a numerical renormalization group study of the device.

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S. J. Chorley, M. R. Galpin, F. W. Jayatilaka, C. G. Smith, D. E. Logan, M. R. Buitelaar. 2012-09-17. Tunable Kondo physics in a carbon nanotube double quantum dot. https://doi.org/10.1103/physrevlett.109.156804

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