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arXiv · 0906.2933

Kondo screening cloud in the single-impurity Anderson model: A density matrix renormalization group study

Andreas Holzner·Ian P. McCulloch·Ulrich Schollwöck·Jan von Delft·Fabian Heidrich-Meisner
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Abstract

A magnetic moment in a metal or in a quantum dot is, at low temperatures, screened by the conduction electrons through the mechanism of the Kondo effect. This gives rise to spin-spin correlations between the magnetic moment and the conduction electrons, which can have a substantial spatial extension. We study this phenomenon, the so-called Kondo cloud, by means of the density matrix renormalization group method for the case of the single-impurity Anderson model. We focus on the question whether the Kondo screening length, typically assumed to be proportional to the inverse Kondo temperature, can be extracted from the spin-spin correlations. For several mechanisms -- the gate potential and a magnetic field -- which destroy the Kondo effect, we investigate the behavior of the screening cloud induced by these perturbations.

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Andreas Holzner, Ian P. McCulloch, Ulrich Schollwöck, Jan von Delft, Fabian Heidrich-Meisner. 2009-06-16. Kondo screening cloud in the single-impurity Anderson model: A density matrix renormalization group study. https://doi.org/10.1103/physrevb.80.205114

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