Inelastic scattering from quantum impurities

Abstract

We review the non-perturbative theoretical framework set up recently to compute the inelastic scattering cross section from quantum impurities [G. Zaránd et al., Phys. Rev. Lett. 93, 107204 (2004)] and show how it can be applied to a number of quantum impurity models. We first use this method for the S = 1/2 single-channel Kondo model and the Anderson model. In both cases, a large plateau is found in the inelastic scattering rate for incoming energies above T K , and a quasi-linear regime appears in the energy range 0.05 T K < ω < 0.5 T K , in agreement with the experimental observations. We also present results for the 2-channel Kondo model, the prototype of all non-Fermi liquid models, and show that there half of the scattering remains inelastic even at the Fermi energy.

Transmission phase shifts of Kondo impurities

“…Expressions for the dephasing rate and the ratio between the inelastic scattering cross section and the total cross section, both related to the normalized visibility η, appear in the literature [42][43][44][45] . We show that spin summation has a crucial effect on ϕ t and η of Kondo impurities.…”