A new perturbation treatment applied to the transport through a quantum dot

Luis Craco; Kicheon Kang

doi:10.1103/physrevb.59.12244

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A new perturbation treatment applied to the transport through a quantum dot

Luis Craco·Kicheon Kang

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Abstract

Resonant tunnelling through an Anderson impurity is investigated by employing a new perturbation scheme at nonequilibrium. This new approach gives the correct weak and strong coupling limit in $U$ by introducing adjustable parameters in the self-energy and imposing self-consistency of the occupation number of the impurity. We have found that the zero-temperature linear response conductance agrees well with that obtained from the exact sum rule. At finite temperature the conductance shows a nonzero minimum at the Kondo valley, as shown in recent experiments. The effects of an applied bias voltage on the single-particle density of states and on the differential conductances are discussed for Kondo and non-Kondo systems.

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Luis Craco, Kicheon Kang. 1998-11-09. A new perturbation treatment applied to the transport through a quantum dot. https://doi.org/10.1103/physrevb.59.12244

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