Poor man's scaling: anisotropic Kondo and Coqblin--Schrieffer models

E. Kogan

doi:10.1088/2399-6528/aad484

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arXiv · 1801.05233

Poor man's scaling: anisotropic Kondo and Coqblin--Schrieffer models

E. Kogan

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Abstract

We discuss Kondo effect for a general model, describing a quantum impurity with degenerate energy levels, interacting with a gas of itinerant electrons, and derive scaling equation to the second order for such a model. We show how the scaling equation for the spin-anisotropic Kondo model with the power law density of states (DOS) for itinerant electrons follows from the general scaling equation. We introduce the anisotropic Coqblin--Schrieffer model, apply the general method to derive scaling equation for that model for the power law DOS, and integrate the derived equation analytically.

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E. Kogan. 2018-08-01. Poor man's scaling: anisotropic Kondo and Coqblin--Schrieffer models. https://doi.org/10.1088/2399-6528%2Faad484

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