Template for Abstract of ICMAGMA-2014

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Increase in Ferromagnetism in Fe Doped PrCrO3
Perovskite
Venugopal Rao.B 1, Vittal Prasad.B 2, Narsinga Rao.G3, Chou F C3, Suresh Babu D1,*.
1Department of Physics, Osmania University,Hyderabad,India,[email protected]
2 Department of Physics, Government Polytechnic ( Gomaram Village),[email protected]
3 Centre for Condensed Matter Physics,National Taiwan university,Taipei,Taiwan,R.O.C,[email protected]
1,* Corresponding Author, E-mail: [email protected]
Abstract
PrCr1-xFexO3 samples were prepared by citric acid
route. These samples were characterized by XRD SEM.
The samples behave as Curie - Weiss paramagnetism
above transition temperatures. The frustration of coexistence of anti - ferromagnetism and ferromagnetism
leads to decrease of magnetic ordering transition
temperature from 240K (x=0) to 98K (x=0.8) in these
samples. The Fe3+ substitution in Cr3+ site increases the
Cr-O-Fe ferromagnetic super exchange interaction and
thus increase in magnetic moments,with maximum at
x=0.8.
Keywords: Orthochromites, Multiferroics, Super exchange
interaction, Neel temperature, Canted anti ferromagnetism.
Introduction
The materials belonging to multiferroic
group ABO3 are attracting importance because of
their potential applications. The availability of
transition metal‘d’ electrons in the perovskite oxides
are necessary for magnetism. The materials of
ReCrxFe1-xO3 with ABO3 perovskite structure have
possible strong ferromagnetic coupling [ ]. According
to Kanamori-Goodenough rule, Fe(d5)-O-Cr(d3)
would show FM behavior through superexchange
interaction when Fe and Cr were arranged orderly at
B-sites. Hence, it is proposed to study the
magnetization properties of Fe doped PrCrO3.
Results and Discussions
The Samples were prepared by citric acid
method and characterized by XRD, SEM. The
magnetization studies were performed using MPMS
made Quantum design Inc.
The prepared samples have shown the formation of
single phase orthorhombic system and increase of
lattice parameters with Fe3+ doping. The average grain
size of the samples is found to be 150nm and the grain
size has increased with increase in Fe Content.The
temperature dependent magnetization measurements
(Fig 1) have shown the existence of two transition
temperatures as TN1and TN2. The values of TN1
decreased from 240K to 98K with increase in ‘x’ from
0.0 to 0.8 due to the presence of Fe-O-Cr FM
interaction. The TN2 has shown the fall from 20K to
10K . The samples behave as paramagnetic above
Figure 1: Temperature dependent magnetization
measurements.
TN1.The field dependent magnetization measurements
shown the increase of magnetization due to FM
interaction leading to FM clusters and reaches
maximum at x=0.8( Fig 2) .
Figure. 2: Variation of Mmax and Mr of the samples
References:
1) K.Miura,K.Terakura,Phys.rev B,2001,63,104402.
2) P.Baettig,C.Ederer,N A Spaldin,Phys.Rev B
2005,72,214105.
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