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The Kondo Box: A Magnetic Impurity in an Ultrasmall Metallic Grain

Wolfgang B. Thimm·Johann Kroha·Jan von Delft
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Abstract

We study the Kondo effect generated by a single magnetic impurity embedded in an ultrasmall metallic grain, to be called a ``Kondo box''. We find that the Kondo resonance is strongly affected when the mean level spacing in the grain becomes larger than the Kondo temperature, in a way that depends on the parity of the number of electrons on the grain. We show that the single-electron tunneling conductance through such a grain features Kondo-induced Fano-type resonances of measurable size, with an anomalous dependence on temperature and level spacing.

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Wolfgang B. Thimm, Johann Kroha, Jan von Delft. 1998-09-30. The Kondo Box: A Magnetic Impurity in an Ultrasmall Metallic Grain. https://doi.org/10.1103/physrevlett.82.2143

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