Oxygen vacancies effect on phase separation in Pr0.5Ca0.2Sr0.3MnO3-δ

We study the effect of the introduction of a controlled amount of oxygen vacancies on the magnetic and transport properties of the phase separated manganite Pr0.5Ca0.2Sr0.3MnO3−δ, for δ=0 and 0.01. This compound presents a paramagnetic to ferromagnetic (FM) transition below TC∼240 K, and then to a c...

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Detalles Bibliográficos
Autores: Niebieskikwiat, Dario Gabriel, Caneiro, Alberto, Sanchez, Rodolfo Daniel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2003
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/68588
Acceso en línea:http://hdl.handle.net/11336/68588
Access Level:acceso abierto
Palabra clave:Ferromagnetism
vacancies
antiferromagnetism
magnetoresistance
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:We study the effect of the introduction of a controlled amount of oxygen vacancies on the magnetic and transport properties of the phase separated manganite Pr0.5Ca0.2Sr0.3MnO3−δ, for δ=0 and 0.01. This compound presents a paramagnetic to ferromagnetic (FM) transition below TC∼240 K, and then to a charge-ordered (CO) and antiferromagnetic (AFM) phase at TCO∼175 K. However, below TCO an appreciable FM component (∼20%) still survives, related to a FM volume immersed within the CO/AFM matrix. At low temperatures, in the mainly CO phase, the introduction of oxygen vacancies enhances the FM ordering, with the consequent decrease of resistivity and magnetoresistance (MR). On the contrary, in the FM phase (in the range TCO<T<TC) the magnetization is reduced and the resistivity and MR increase. These results are discussed in the frame of percolative transport in metal–insulator mixtures, and frustrated double exchange interaction due to the interruption of some Mn–O–Mn chains.