Electronic structure calculations combining the local density approximation with an exact diagonalization of the Anderson impurity model show intermediate 5f5–5f6-valence ground state and delocalization of the 5f5 multiplet of the Pu atom 5f-shell in PuCoGa5, and δ-Pu. The 5f-local magnetic moment is compensated by a moment formed in the surrounding cloud of conduction electrons. For PuCoGa5 and δ-Pu the compensation is complete and the Anderson impurity ground state is a singlet. This can be important for analyses of the superconducting pairing mechanism in PuCoGa5. It is likely that in PuCoGa5 unconventional d-wave superconductivity is mediated by the 5f-states valence fluctuations, rather than antiferromagnetic fluctuations.
Les méthodes de calcul des structures électroniques qui combinent l'approximation de densité locale avec une diagonalisation exacte du modèle d'impureté d'Anderson prévoyaient, pour δ-Pu et pour PuCoGa5, un état fondamental de valence intermédiaire 5f5–5f6, ainsi qu'une délocalisation de la couche électronique 5f du Pu. Le moment magnétique local 5f est compensé par un moment formé dans le milieu des électrons de conduction. Pour PuCoGa5 et δ-Pu, cette compensation est complète et l'état fondamental de l'impureté d'Anderson est un singulet non magnétique. Ce résultat peut avoir des conséquences importantes sur l'analyse des mécanismes de couplage de Cooper dans PuCoGa5. Il est possible que la supraconductivité non conventionnelle de symétrie d dans PuCoGa5 soit véhiculée par des fluctuations de valence des états 5f plutôt que par des fluctuations magnétiques.
Mots-clés : Structure électronique, Corrélations électroniques fortes, Photoémission, Supraconductivité non conventionnelle
Alexander B. Shick 1; Jindrich Kolorenč 1
@article{CRPHYS_2014__15_7_640_0,
author = {Alexander B. Shick and Jindrich Koloren\v{c}},
title = {Role of electron correlation effects in {\protect\emph{\ensuremath{\delta}}-Pu} and {{\textquotedblleft}115{\textquotedblright}-Pu-based} unconventional superconductors},
journal = {Comptes Rendus. Physique},
pages = {640--647},
publisher = {Elsevier},
volume = {15},
number = {7},
year = {2014},
doi = {10.1016/j.crhy.2014.06.006},
language = {en},
}
TY - JOUR AU - Alexander B. Shick AU - Jindrich Kolorenč TI - Role of electron correlation effects in δ-Pu and “115”-Pu-based unconventional superconductors JO - Comptes Rendus. Physique PY - 2014 SP - 640 EP - 647 VL - 15 IS - 7 PB - Elsevier DO - 10.1016/j.crhy.2014.06.006 LA - en ID - CRPHYS_2014__15_7_640_0 ER -
Alexander B. Shick; Jindrich Kolorenč. Role of electron correlation effects in δ-Pu and “115”-Pu-based unconventional superconductors. Comptes Rendus. Physique, Emergent phenomena in actinides, Volume 15 (2014) no. 7, pp. 640-647. doi : 10.1016/j.crhy.2014.06.006. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2014.06.006/
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