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.
1 More- Received 19 June 2009
DOI:https://doi.org/10.1103/PhysRevB.80.205114
©2009 American Physical Society