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Poor mans scaling: anisotropic Kondo and Coqblin--Schrieffer models

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 نشر من قبل Eugene Kogan
 تاريخ النشر 2018
  مجال البحث فيزياء
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 تأليف E. Kogan




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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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