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dc.contributor.author
Sposetti, Cintia Natalia
dc.contributor.author
Manuel, Luis Oscar
dc.contributor.author
Roura Bas, Pablo Gines
dc.date.available
2018-06-29T18:34:11Z
dc.date.issued
2016-08
dc.identifier.citation
Sposetti, Cintia Natalia; Manuel, Luis Oscar; Roura Bas, Pablo Gines; Qualitative breakdown of the noncrossing approximation for the symmetric one-channel Anderson impurity model at all temperatures; American Physical Society; Physical Review B: Condensed Matter and Materials Physics; 94; 8; 8-2016; 851391-851398
dc.identifier.issn
1098-0121
dc.identifier.uri
http://hdl.handle.net/11336/50749
dc.description.abstract
The Anderson impurity model is studied by means of the self-consistent hybridization expansions in its noncrossing (NCA) and one-crossing (OCA) approximations. We have found that for the one-channel spin-1/2 particle-hole symmetric Anderson model, the NCA results are qualitatively wrong for any temperature, even when the approximation gives the exact threshold exponents of the ionic states. Actually, the NCA solution describes an overscreened Kondo effect, because it is the same as for the two-channel infinite-U single-level Anderson model. We explicitly show that the NCA is unable to distinguish between these two very different physical systems, independently of temperature. Using the impurity entropy as an example, we show that the low-temperature values of the NCA entropy for the symmetric case yield the limit Simp(T=0)→ln2, which corresponds to the zero temperature entropy of the overscreened Kondo model. Similar pathologies are predicted for any other thermodynamic property. On the other hand, we have found that the OCA approach lifts the artificial mapping between the models and restores correct properties of the ground state, for instance, a vanishing entropy at low enough temperatures Simp(T=0)→0. Our results indicate that the very well known NCA should be used with caution close to the symmetric point of the Anderson model.
dc.format
application/pdf
dc.language.iso
eng
dc.publisher
American Physical Society
dc.rights
info:eu-repo/semantics/openAccess
dc.rights.uri
https://creativecommons.org/licenses/by/2.5/ar/
dc.subject
Kondo Effect
dc.subject
Anderson Model
dc.subject
Non Crossing Approximation
dc.subject.classification
Astronomía
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Ciencias Físicas
dc.subject.classification
CIENCIAS NATURALES Y EXACTAS
dc.title
Qualitative breakdown of the noncrossing approximation for the symmetric one-channel Anderson impurity model at all temperatures
dc.type
info:eu-repo/semantics/article
dc.type
info:ar-repo/semantics/artículo
dc.type
info:eu-repo/semantics/publishedVersion
dc.date.updated
2018-06-26T22:25:12Z
dc.identifier.eissn
2469-9969
dc.journal.volume
94
dc.journal.number
8
dc.journal.pagination
851391-851398
dc.journal.pais
Estados Unidos
dc.journal.ciudad
Maryland
dc.description.fil
Fil: Sposetti, Cintia Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
dc.description.fil
Fil: Manuel, Luis Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina
dc.description.fil
Fil: Roura Bas, Pablo Gines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Gerencia Química. CAC; Argentina
dc.journal.title
Physical Review B: Condensed Matter and Materials Physics
dc.relation.alternativeid
info:eu-repo/semantics/altIdentifier/url/https://journals.aps.org/prb/abstract/10.1103/PhysRevB.94.085139
dc.relation.alternativeid
info:eu-repo/semantics/altIdentifier/doi/http://dx.doi.org/10.1103/PhysRevB.94.085139
dc.relation.alternativeid
info:eu-repo/semantics/altIdentifier/url/https://arxiv.org/abs/1608.03018
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