Abstract
The exchange striction model is invoked to derive an expression for the entropy of ferromagnetic materials undergoing first- and second-order magnetic phase transitions. The magnetocaloric and barocaloric effects are calculated for the ferromagnet La(Fe0.88Si0.12)13 undergoing a first-order phase transition. The calculated results are in fair agreement with experimental data. The ferromagnet La(Fe0.88Si0.12)13 is used as an example to predict the changes in magnetic and magnetocaloric properties associated with gradual increase in the magnetoelastic coupling constant (i.e., with passage from first- to second-order magnetic transition region). It is shown that stronger magnetoelastic coupling leads to stronger magnetocaloric effects and changes their dependence on magnetic field and pressure. Expressions are obtained for the maximum field- and pressure-induced entropy changes. An analysis is presented of the mechanism responsible for the increase in magnetocaloric and barocaloric effects associated with change from the second- to first-order magnetic phase transition.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
A. M. Tishin, in Handbook of Magnetic Materials, Ed. by K. H. J. Bushow (Elsevier, Amsterdam, 1999), Vol. 12, p. 395.
V. K. Pecharsky, K. A. Gschneidner, A. O. Pecharsky, and A. M. Tishin, Phys. Rev. B: Condens. Matter 64, 144406 (2001).
E. Z. Valiev, Fiz. Met. Metalloved. 104(1), 12 (2007) [Phys. Met. Metallogr. 104 (1), 8 (2007)].
É. Z. Valiev, in Proceedings of the International Interdisciplinary Symposium “Structure Magnetic Ordering in Solids” (Multiferroics-2007), Rostov-on-Don, Loo, Russia, 2007 (Rostov-on-Don, 2007), p. 52.
C. P. Bean and D. S. Rodbell, Phys. Rev. 126, 104 (1962).
A. Fujita, S. Fujieda, K. Fukamichi, H. Mitamura, and T. Goto, Phys. Rev. B: Condens. Matter 65, 014410 (2001).
A. Fujita, Y. Akamatsu, and K. Fukamichi, J. Appl. Phys. 85, 4756 (1999).
A. Fujita, S. Fujieda, Y. Hasegawa, and K. Fukamichi, Phys. Rev. B: Condens. Matter 67, 104416 (2003).
K. A. Müller, F. Fauth, S. Fischer, M. Koch, A. Furrer, and Ph. Lacorre, Appl. Phys. Lett. 73, 1056 (1998).
H. Yamada and T. Goto, Phys. Rev. B: Condens. Matter 68, 184417 (2003).
P. J. von Ranke, N. A. de Oliveira, and S. Gama, J. Magn. Magn. Mater. 277, 78 (2004).
V. S. Amaral and J. S. Amaral, J. Magn. Magn. Mater. 272–276, 2104 (2004).
P. J. von Ranke, S. Gama, A. A. Coelho, A. de Campos, A. Magnus G. Carvalho, F. C. G. Gandra, and N. A. de Oliveira, Phys. Rev. B: Condens. Matter 73, 014415 (2006).
J. D. Zou, B. G. Shen, and J. R. Sun, J. Phys: Condens. Matter 19, 196220 (2007).
N. A. de Oliveira and P. J. von Ranke, Phys. Rev. B: Condens. Matter 77, 214439 (2008).
E. Z. Valiev and A. Z. Menshikov, J. Magn. Magn. Mater. 46, 199 (1984).
É. A. Zavadskioe and V. I. Val’kov, Magnetic Phase Transitions (Naukova Dumka, Kiev, 1980) [in Russian].
Yu. A. Izyumov and V. N. Syromyatnikov, Phase Transitions and Crystal Symmetry (Nauka, Moscow, 1984; Kluwer, Dordrecht, The Netherlands, 1990).
E. Z. Valiev and F. S. Shemet’ev, Fiz. Met. Metalloved. 102(2), 139 (2006) [Phys. Met. Metallogr. 102 (2), 127 (2006)].
F. X. Hu, B. G. Shen, J. R. Sun, Z. H. Cheng, G. H. Rao, and X. X. Zhang, Appl. Phys. Lett. 78, 3675 (2001).
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © É. Z. Valiev, 2009, published in Zhurnal Éksperimental’noĭ i Teoreticheskoĭ Fiziki, 2009, Vol. 135, No. 2, pp. 314–321.
Rights and permissions
About this article
Cite this article
Valiev, É.Z. Entropy and magnetocaloric effects in ferromagnets undergoing first- and second-order magnetic phase transitions. J. Exp. Theor. Phys. 108, 279–285 (2009). https://doi.org/10.1134/S1063776109020101
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S1063776109020101