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arXiv · 1005.5154

Coherence scale of coupled Anderson impurities

Lijun Zhu·Jian-Xin Zhu
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Abstract

For two coupled Anderson impurities, two energy scales are present to characterize the evolution from local moment state of the impurities to either of the inter-impurity singlet or the Kondo singlet ground states. The high energy scale is found to deviate from the single-ion Kondo temperature and rather scales as Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction when it becomes dominant. We find that the scaling behavior and the associated physical properties of this scale are consistent with those of a coherence scale defined in heavy fermion systems.

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Lijun Zhu, Jian-Xin Zhu. 2010-11-30. Coherence scale of coupled Anderson impurities. https://doi.org/10.1103/physrevb.83.195103

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