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Frequency-dependent transport through a quantum dot in the Kondo regime

M. Sindel·W. Hofstetter·J. von Delft·M. Kindermann
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Abstract

We study the AC conductance and equilibrium current fluctuations of a Coulomb blockaded quantum dot. A relation between the equilibrium spectral function and the linear AC conductance is derived which is valid for frequencies well below the charging energy of the quantum dot. Frequency-dependent transport measurements can thus give experimental access to the Kondo peak in the equilibrium spectral function of a quantum dot. We illustrate this in detail for typical experimental parameters using the numerical renormalization group method in combination with the Kubo formalism.

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M. Sindel, W. Hofstetter, J. von Delft, M. Kindermann. 2005-05-24. Frequency-dependent transport through a quantum dot in the Kondo regime. https://doi.org/10.1103/physrevlett.94.196602

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