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arXiv · 0802.0280

Friedel oscillations and the Kondo screening cloud

Ian Affleck·Laszlo Borda·Hubert Saleur
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Abstract

We show that the long distance charge density oscillations in a metal induced by a weakly coupled spin-1/2 magnetic impurity exhibiting the Kondo effect are given, at zero temperature, by a universal function F(r/xi_K) where r is the distance from the impurity and xi_K, the Kondo screening cloud size =v_F/T_K, where v_F is the Fermi velocity and T_K is the Kondo temperature. F is given by a Fourier-like transform of the T-matrix. Analytic expressions for F(r/xi_K) are derived in both limits r much less than xi_K and r much greater than xi_K and F is calculated for all r/xi_K using numerical methods.

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Ian Affleck, Laszlo Borda, Hubert Saleur. 2008-04-30. Friedel oscillations and the Kondo screening cloud. https://doi.org/10.1103/physrevb.77.180404

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