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arXiv · 0911.5202

Crossover from dilute-Kondo system to heavy-fermion system

Hiroshi Watanabe·Masao Ogata
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Abstract

Ground state properties of a Kondo lattice model with random configuration of $f$ electrons are investigated with a variational Monte Carlo method. We show that the crossover from a dilute-Kondo system to a heavy-fermion system occurs when the density of $c$ and $f$ electrons ($n_c$, $n_f$) become comparable, $n_f\lesssim n_c$. In the heavy-fermion region, the correlation between $f$ electrons is strong and the $f$ electrons themselves greatly contribute to the screening of other $f$-electron moments. We propose that the character of Kondo screening changes from "individual" to "collective" across the crossover.

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Hiroshi Watanabe, Masao Ogata. 2009-11-27. Crossover from dilute-Kondo system to heavy-fermion system. https://doi.org/10.1103/physrevb.81.113111

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