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arXiv · 1312.7266

Comment on "Conductance scaling in Kondo-correlated quantum dots: Role of level asymmetry and charging energy"

A. A. Aligia
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Abstract

In a recent work [L. Merker, S. Kirchner, E. Munoz, and T. A. Costi, Phys. Rev. B 87, 165132 (2013)], the authors compared results of numerical renormalization group and a perturbative approach for the dependence on temperature T and magnetic field B of the conductance through a quantum dot described by the impurity Anderson model, for small T and B. We show that the equation used to extract the dependence on B from NRG results is incorrect out of the particle-hole symmetric case. As a consequence, in the Kondo regime, the correct NRG results have a weaker dependence on B and the disagreement between both approaches increase.

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A. A. Aligia. 2013-12-27. Comment on "Conductance scaling in Kondo-correlated quantum dots: Role of level asymmetry and charging energy". https://doi.org/10.1103/physrevb.90.077101

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