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Universal dephasing rate due to diluted Kondo impurities

T. Micklitz·A. Altland·T. A. Costi·A. Rosch
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Abstract

We calculate the dephasing rate due to magnetic impurities in a weakly disordered metal as measured in a weak localization experiment. If the density n_S of magnetic impurities is sufficiently low, the dephasing rate 1/tau_phi is a universal function, 1/tau_phi = (n_S/nu) f(T/T_K), where T_K is the Kondo temperature and nu the density of states. We show that inelastic vertex corrections with a typical energy transfer Delta E are suppressed by powers of 1/(tau_phi Delta E) proportional to n_S. Therefore the dephasing rate can be calculated from the inelastic cross section proportional to pi nu Im T- |pi nu T|^2, where T is the T-matrix which is evaluated numerically exactly using the numerical renormalization group.

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T. Micklitz, A. Altland, T. A. Costi, A. Rosch. 2006-05-18. Universal dephasing rate due to diluted Kondo impurities. https://doi.org/10.1103/physrevlett.96.226601

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