Diary of Magnetism and Permanent magnetic Materials 324 (2012) 3351–3355
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Investigation of magnetocaloric impact in La0. 45Pr0. 25Ca0. 3MnO3 by magnetic, differential box scanning calorimetry and heat analysis
Meters. Aparnadevi, S. K. Barik, R. Mahendiran n
Department of Physics, 2 Science Drive a few, National College or university of Singapore, Lower Kent Ridge Highway, Singapore-117 452, Singapore
a r big t i c l at the i n f to
Received 7 Drive 2012
Available online 5 06 2012
We investigated magnetocaloric effect in La0. 45Pr0. 25Ca0. 3MnO3 by direct methods (changes in temp and important heat) and indirect method (magnetization isotherms). This compound undergoes a ﬁrst-order paramagnetic to ferromagnetic transition with TC ¼ 200 T upon cooling down. The paramagnetic phase becomes unstable and it changes into a ferromagnetic phase underneath the application of magnet ﬁeld, which results in a ﬁeld-induced metamagnetic move (FIMMT). The FIMMT is definitely accompanied by relieve of important heat and temperature from the sample because evidenced by differential checking calorimetry and thermal evaluation experiments. A large magnetic entropy change of DSm ¼ À several. 2 M kg À 1 T À 1 at T¼ 212. your five K and refrigeration capacity of 228 J kilogram À one particular are found for a ﬁeld transform of DH¼ 5 T. It is suggested that destruction of magnetic polarons and growth of ferromagnetic period accompanied by a lattice volume alter with increasing magnetic ﬁeld is responsible for the large magnetocaloric result in this compound.
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1 ) Introduction
In recent years, magnetic refrigeration has drawn considerable focus because it is considered to be a viable option to conventional gas compression centered refrigeration because of the facts it does not emit environmentally hazardous gases and is energy efﬁcient . Magnetic refrigeration makes use of the reality temperature of a magnetic material changes upon a change in
external permanent magnetic ﬁeld. Using a magnet ﬁeld isothermally followed by adiabatic removal of magnetic ﬁeld reduce and increases the magnetic entropy (DSm) of a ferromagnetic
test, respectively. While the permanent magnet entropy raises upon adiabatic removal of permanent magnetic ﬁeld, essudato entropy has to decrease to save the total entropy and hence the sample
cools down. The adiabatic temperatures change (DTad) or isothermal magnetic entropy change (DSm) due to a change in magnet ﬁeld is known as the magnetocaloric effect (MCE). The MCE reaches a maximum worth at the ferromagnetic Curie temp (TC) and it is signiﬁcantly enhanced in ingredients that present ﬁrst-order magnetic transition. A ﬁrst-order phase transition is usually accompanied by an abrupt amount change with or without a change in
strength symmetry throughout the phase transition. Large MCE due to magneto-structural transition was discovered in intermetallic alloys such as Gd5Si2Ge24 , NiMnGa , alloys and in addition in the
Corresponding writer. Tel.: þ65 6516 2616; fax: þ65 6777 6126. E-mail addresses: [email protected] edu. sg (R. Mahendiran).
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antiferromagnetic manganite Pr0. 46Sr0. 54MnO3 . Materials just like MnFeP0. 45As0. 55  and LaFe13 À xSix  which in turn undergo magnetoelastic phase change without any change in crystal symmetry also present high MCE values. The effect of pressure in joining or decoupling of magnetic and crystallographic transitions is reported .
Manganites having the general formula R1 À xAxMnO3 (R is known as a
trivalent uncommon earth ion and A is a divalent alkaline globe ion) can also be considered to be promising candidates for magnetic refrigeration due to huge...
References:  K. A. Gschneidner Junior., V. K. Pecharsky, A. O. Tsokol, Reports about Progress in
Physics 68 (2005) 1479.
 Farrenheit. Hu, W. Shen, L. Sun, Utilized Physics Albhabets 76 (2000) 3460.
 V. M. Naik, H. K. Barik, R. Mahendiran, B. Raveau, Applied Physics Letters 98
M. Aparnadevi et approach. / Diary of Magnetism and Permanent magnet Materials 324 (2012) 3351–3355
 N. G
 L. Caron, N. Big t. Trung, At the. Bruck, Physical Review B 84 (2011) 020414.
 For a review on MCE in manganites, see M. H. Phan, S. C. Yu, Log of
Magnetism and Magnet Materials 308 (2007) 325.
 J. C. Debnath, R. Zeng, J. L. Kim, S i9000. X. Dou, Journal of Applied Physics 107 (2010)
 Y. Sunshine, X. Xu, Y. They would. Zhang, Journal of Magnetism and Magnet Materials 219
A. In. Ulyanov, M. S. Ellie, G. Meters. Shin, Con. M. Kang, S. I actually. Yoo, Record of Physics D:
Used Physics 45 (2007) 123.
 A. R. Dinesen, S. Linderoth, S. Morup, Journal of Magnetism and Magnetic
Components 253 (2002) 28;
A. R. Dinesen, S. Linderoth, S. Morup, Journal of Physics: Compacted Matter 18
 Unces. M. Wang, G. Ni, Q. Con. Xu, H. Sang, Con. W. Ni, Journal of Applied Physics 90
Physics Letters ninety five (2009) 092506.
 T. Jeppesen, S. Linderoth, In. Pryds, D. Theil Kuhn, J. Buch Jensen, Review of
Scientiﬁc Devices 79 (2008) 083901;
seventy nine (2008) 063907.
 M. Marcos, N. Casanova, X. Batlle, A. Labarta, A. Planes, D. Manosa, Report on
Scientiﬁc Musical instruments 74 (2003) 4768.
 M. Quintero, J. Sacanell, L. Ghivelder, A. M. Gomes, A. G. Leyva, F. Parisi,
Applied Physics Letters ninety-seven (2010) 121916.
 Versus. Basso, Journal of Physics Condensed Matter 23 (2011) 226004.
 D. Electronic. Cox, L. G. Radaelli, M. Marezio, S. –W. Cheong, Physical Review N 57