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Multichannel Kondo Screening in a One-Dimensional Correlated Electron System

A. A. Zvyagin·H. Johannesson·M. Granath
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Abstract

We present the exact Bethe Ansatz solution of a multichannel model of one- dimensional correlated electrons coupled antiferromagnetically to a magnetic impurity of arbitrary spin S. The solution reveals that interactions in the bulk make the magnetic impurity drive both spin and charge fluctuations, producing a mixed valence at the impurity site, with an associated effective spin S_eff > S in the presence of a magnetic field. The screening of the impurity spin is controlled by its size independently of the number of channels, in contrast to the multichannel Kondo effect for free electrons.

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A. A. Zvyagin, H. Johannesson, M. Granath. 1997-12-08. Multichannel Kondo Screening in a One-Dimensional Correlated Electron System. https://doi.org/10.1209/epl%2Fi1998-00567-2

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