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Disordered Kondo Nanoclusters: Effect of Energy Spacing

C. Verdozzi·Y. Luo·Nicholas Kioussis
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Abstract

Exact diagonalization results for Kondo nanoclusters alloyed with mixed valence impurities show that tuning the {\it energy spacing}, $Δ$, drives the system from the Kondo to the RKKY regime. The interplay of $Δ$ and disorder gives rise to a $Δ$ versus concentration T=0 phase diagram very rich in structure, where regions with prevailing Kondo or RKKY correlations alternate with domains of ferromagnetic order. The local Kondo temperatures, $T_K$, and RKKY interactions depend strongly on the local environment and are overall {\it enhanced} by disorder, in contrast to the hypothesis of ``Kondo disorder'' single-impurity models.

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C. Verdozzi, Y. Luo, Nicholas Kioussis. 2003-07-19. Disordered Kondo Nanoclusters: Effect of Energy Spacing. https://doi.org/10.1103/physrevb.70.132404

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