Magnetic, electron magnetic resonance and optical studies of $Pr_{0.7}Pb_{0.3}MnO_3$ nanoparticles

Rao, SS and Padmanabhan, B and Elizabeth, Suja and Bhat, HL and Bhat, SV (2008) Magnetic, electron magnetic resonance and optical studies of $Pr_{0.7}Pb_{0.3}MnO_3$ nanoparticles. In: Journal of Physics D: Applied Physics, 41 (15). 155011-1-155011-8.

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Abstract

In this paper we present the preparation and physical property studies on $Pr_{0.7}Pb_{0.3}MnO_3$(PPMO) nanoparticles with an average grain size of 5 nm. We find from SQUID magnetometry measurements that the Curie temperature $(T_C)$ remains unaltered at 205K with decrease in the particle size down to 5 nm in comparison with bulk $T_C$ (200 K). From electron magnetic resonance (EMR) measurements, it is found that PPMO nanoparticles are more homogeneous than bulk PPMO. Only one EMR signal is observed down to 4K in PPMO with an average particle size of 5 nm in contrast to the two EMR signal behaviour observed in bulk PPMO (200–240 K). The origin of the two EMR signals in the bulk was attributed to possible phase separation Padmanabhan B etal 2007 Physica B 398 107). Such a phase separation is therefore concluded to be absent in nano-PPMO. In addition, temperature-dependent optical phonon measurements performed on 5 nm PPMO nanoparticles indicate the insulator–metal transition $(T_{MI} = 230 K)$, which is nearly the same as that of the bulk sample $(T_{MI} = 235 K)$.

Item Type:	Journal Article
Publication:	Journal of Physics D: Applied Physics
Publisher:	Institute of Physics
Additional Information:	Copyright of this article belongs to Institute of Physics.
Department/Centre:	Division of Physical & Mathematical Sciences > Physics
Date Deposited:	20 Oct 2008 05:13
Last Modified:	19 Sep 2010 04:51
URI:	http://eprints.iisc.ac.in/id/eprint/16150

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