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Oscillation and suppression of Kondo temperature by RKKY coupling in two-site Kondo systems

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 نشر من قبل Johann Kroha
 تاريخ النشر 2016
  مجال البحث فيزياء
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We apply our recently developed, selfconsistent renormalization group (RG) method to STM spectra of a two-impurity Kondo system consisting of two cobalt atoms connected by a one-dimensional Cu chain on a Cu surface. This RG method was developed to describe local spin screening in multi-impurity Kondo systems in presence of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction. Using the RKKY interaction of a one-dimensional chain, we explain the experimentally observed suppression and oscillation of the Kondo temperature, $T_K(y)$, as a function of the length of the chain and the corresponding RKKY interaction parameter $y$, regardless of the RKKY coupling being ferromagnetic or antiferromagnetic.



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