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Zero-field splitting of Kondo resonances in a carbon nanotube quantum dot

J. Nygard·W. F. Koehl·N. Mason·L. DiCarlo·C. M. Marcus
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Abstract

We present low-temperature electron transport measurements on a single-wall carbon nanotube quantum dot exhibiting Kondo resonances at low temperature. Contrary to the usual behavior for the spin-1/2 Kondo effect we find that the temperature dependence of the zero bias conductance is nonmonotonic. In nonlinear transport measurements low-energy splittings of the Kondo resonances are observed at zero magnetic field. We suggest that these anomalies reflect interactions between the nanotube and a magnetic (catalyst) particle. The nanotube device may effectively act as a ferromagnetically contacted Kondo dot.

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J. Nygard, W. F. Koehl, N. Mason, L. DiCarlo, C. M. Marcus. 2004-10-25. Zero-field splitting of Kondo resonances in a carbon nanotube quantum dot. https://arxiv.org/abs/cond-mat/0410467

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