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A New Mean-Field Theory of the Kondo Resonance at Finite Bias

Jung Hoon Han
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Abstract

We introduce a new slave-boson mean-field treatment of the Kondo effect in a quantum dot attached to the leads, when the bias voltage across the leads is finite. The model employs two slave boson and two pseudo-fermion operators to express the localized electron. The solution of the mean-field equations gives in general two resonance peaks pinned to the chemical potential of each lead. The Kondo temperature is shown to scale as $min(\tstar, (\tstar)^2/V)$, where $\tstar$ is the Kondo temperature at equilibrium, and $V$ is the chemical potential difference of the leads.

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Jung Hoon Han. 2003-12-01. A New Mean-Field Theory of the Kondo Resonance at Finite Bias. https://arxiv.org/abs/cond-mat/0312023

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