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SU(4) Kondo Effect in Carbon Nanotubes

Mahn-Soo Choi·Rosa Lopez·Ramon Aguado
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Abstract

We investigate theoretically the non-equilibrium transport properties of carbon nanotube quantum dots. Owing to the two-dimensional band structure of graphene, a double orbital degeneracy plays the role of a pseudo-spin, which is entangled with the spin. Quantum fluctuations between these four degrees of freedom result in an SU(4) Kondo effect at low temperatures. This exotic Kondo effect manifests as a four-peak splitting in the non-linear conductance when an axial magnetic field is applied.

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Mahn-Soo Choi, Rosa Lopez, Ramon Aguado. 2004-11-26. SU(4) Kondo Effect in Carbon Nanotubes. https://doi.org/10.1103/physrevlett.95.067204

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