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Título:
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Interplay between double-exchange, superexchange, and Lifshitz localization in doped manganites
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Autores:
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Alonso, J. L. ;
Fernández Pérez, Luis Antonio ;
Guinea, F. ;
Laliena, V. ;
Martín Mayor, Víctor
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Tipo de documento:
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texto impreso
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Editorial:
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American Physical Society, 2002-09-01
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Dimensiones:
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application/pdf
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Nota general:
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info:eu-repo/semantics/openAccess
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Idiomas:
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Palabras clave:
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Estado = Publicado
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Materia = Ciencias: Física
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Materia = Ciencias: Física: Física-Modelos matemáticos
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Tipo = Artículo
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Resumen:
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Considering the disorder caused in manganites by the substitution Mn?Fe or Ga, we accomplish a systematic study of doped manganites begun in previous papers. To this end, a disordered model is formulated and solved using the variational mean-field technique. The subtle interplay between double exchange, superexchange, and disorder causes similar effects on the dependence of T_(C) on the percentage of Mn substitution in the cases considered. Yet, in La_(2/3)Ca_(1/3)Mn_(1-y)Ga_(y)O_(3) our results suggest a quantum critical point (QCP) for y ? 0.1–0.2, associated to the localization of the electronic states of the conduction band. In the case of La_(x)Ca_(x)Mn_(1-y)Fe_(y)O_(3) (with x = 1/3,3/8) no such QCP is expected.
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En línea:
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https://eprints.ucm.es/38667/1/Fern%C3%A1ndezP%C3%A9rezLuisAntonio35LIBRE.pdf
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