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Hidden Kondo Effect in a Correlated Electron Chain

A. A. Zvyagin·H. Johannesson
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Abstract

We develop a general Bethe Ansatz formalism for diagonalizing an integrable model of a magnetic impurity of arbitrary spin coupled ferro- or antiferromagnetically to a chain of interacting electrons. The method is applied to an open chain, with the exact solution revealing a ``hidden'' Kondo effect driven by forward electron scattering off the impurity. We argue that the so-called ``operator reflection matrices'' proposed in recent Bethe Ansatz studies of related models emulate only forward electron-impurity scattering which may explain the absence of complete Kondo screening for certain values of the impurity-electron coupling in these models.

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A. A. Zvyagin, H. Johannesson. 1998-09-04. Hidden Kondo Effect in a Correlated Electron Chain. https://doi.org/10.1103/physrevlett.81.2751

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