Garga, K. B. and Nordblad, P. and Heinonen, M. and Panwar, N. and Sen, V. and Bondino, F. and Magnano, E. and Carleschi, E. and Parmigiani, F. and Agarwal, S. K. (2008) Study of Sb substitution for Pr in the Pr0.67Ba0.33MnO3 system. Journal of Magnetism and Magnetic Materials, 321 (4). pp. 305-311. ISSN 0304-8853

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Abstract

We study the effect of Sb substitution for Pr in the hole-doped system Pr0.67Ba0.33MnO3 (PBMO) for different doping levels of Sb. The two electrical resistivity transitions observed in the pristine sample PBMO shift to low temperatures on Sb doping with an overall increase in the electrical resistivity. The significant local lattice distortion and the grain boundary effects caused by the large cation size mismatch between Pr3+ and Sb3+ suppresses the double-exchange (DE) interaction and enhances the super-exchange (SE) interaction. The compounds show a significant and increasing value of magnetoresistance at temperatures below the Curie temperature, not expected from the DE model. The Curie temperature decreases with increase in Sb content but the saturation magnetization is little affected by the substitution. The spins, however, stay well aligned in the low-temperature regime. Our X-ray near-edge absorption spectra (XANES) and core level photoemission (XPS) data clearly show the Sb cation to be in +3 state and rule out any possibility of e-doping in our compounds.

Item Type:	Article
Additional Information:	Copyright for this article belongs to M/s Elsevier B.V.
Uncontrolled Keywords:	Manganite; SQUID; X-ray photoemission; XANES; Magnetoresistance; Local lattice distortion; PrMnO(3)
Subjects:	Materials Science Physics
Divisions:	UNSPECIFIED
Depositing User:	Ms Neetu Chandra
Date Deposited:	05 Oct 2012 08:24
Last Modified:	05 Oct 2012 08:24
URI:	http://npl.csircentral.net/id/eprint/664

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