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RKKY interactions in the regime of strong localization

J. A. Sobota·D. Tanaskovic·V. Dobrosavljevic
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Abstract

We study the influence of strong nonmagnetic disorder on the Ruderman-Kittel-Kasuya-Yosida (RKKY) interactions between diluted magnetic moments in metals. We find that the probability distribution for the RKKY interactions assumes strongly non-Gaussian form featuring long tails. Since such distributions cannot be characterized by its moments, we define a \textit{typical} value of the interaction amplitude, which we find to be exponentially suppressed in presence of Anderson localization. Our results present a plausible and physically transparent picture describing how Anderson localization effectively eliminates the long range nature of the RKKY interactions.

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J. A. Sobota, D. Tanaskovic, V. Dobrosavljevic. 2007-12-07. RKKY interactions in the regime of strong localization. https://doi.org/10.1103/physrevb.76.245106

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