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Kondo Effect in Multiple-Dot Systems

Rui Sakano·Norio Kawakami
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Abstract

We study the Kondo effect in multiple-dot systems for which the inter- as well as intra-dot Coulomb repulsions are strong, and the inter-dot tunneling is small. The application of the Ward-Takahashi identity to the inter-dot dynamical susceptibility enables us to analytically calculate the conductance for a double-dot system by using the Bethe-ansatz exact solution of the SU(4) impurity Anderson model. It is clarified how the inter-dot Kondo effect enhances or suppresses the conductance under the control of the gate voltage and the magnetic field. We then extend our analysis to multiple-dot systems including more than two dots, and discuss their characteristic transport properties by taking a triple-dot system as an example.

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Rui Sakano, Norio Kawakami. 2005-02-17. Kondo Effect in Multiple-Dot Systems. https://doi.org/10.1103/physrevb.72.085303

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