arXiv:1802.00407 · Physical review. B./Physical review. B

Two-color Fermi-liquid theory for transport through a multilevel Kondo impurity

D. B. Karki, Christophe Mora, Jan von Delft, Mikhail N. Kiselev

Published May 2, 2018• 25 citations

Abstract

A multiorbital quantum impurity with effective spin S>1/2 connected to several reservoirs of conduction electrons can lead to a Kondo effect, exhibiting multistage screening. The ground state of a prototypical nanoscale device consisting of an S=1 quantum impurity connected to two conducting reservoirs is a spin singlet, formed via a two-stage Kondo screening mechanism. Understanding the equilibrium and nonequilibrium properties of the strong-coupling regime resulting from this two-stage screening has been an open problem for many years. Here, the authors offer a detailed description in terms of an effective local two-color Fermi liquid theory.

DOI: 10.1103/physrevb.97.195403

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