Entropy and magnetocaloric effect in ferrimagnets RCo2

Order, Disorder, and Phase Transition in Condensed System


The equations of state for the magnetic and elastic subsystems of a ferrimagnet are obtained in terms of the exchange–striction model. In the formulas derived for magnetic entropy, it is represented as the sum of the contributions of two magnetic sublattices of the ferrimagnet. One of the main characteristics of the magnetocaloric effect, viz., isothermal variation ΔS iso of the entropy in a magnetic field, is calculated for compounds RCo2 (R = Er, Ho, Dy) that experience a first-order magnetic phase transition and TbCo2 that experiences a second-order magnetic phase transition. It is shown that the calculated values of ΔS iso for these compounds are in satisfactory quantitative agreement with experimental results. The change in the entropy of a ferrimagnet in a strong magnetic field upon a transition from the ferrimagnetic to ferromagnetic ordering is calculated. The peculiarities in the magnetic field dependences of the magnetic entropy of a two-sublattice ferrimagnet are analyzed.


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  1. 1.
    A. Giguere, M. Foldeaki, W. Schnelle, et al., J. Phys.: Condens. Matter 11, 6969 (1999).ADSGoogle Scholar
  2. 2.
    N. H. Duc, D. T. Kim, and P. E. Brommer, Physica B 319, 1 (2002).ADSCrossRefGoogle Scholar
  3. 3.
    N. A. de Oliveira, P. J. von Ranke, M. V. Tovar Costa, et al., Phys. Rev. B 66, 094402 (2002).ADSCrossRefGoogle Scholar
  4. 4.
    N. K. Singh, K. G. Suresh, A. K. Nigam, et al., J. Magn. Magn. Mater. 317, 68 (2007).ADSCrossRefGoogle Scholar
  5. 5.
    J.-D. Zou, B.-G. Shen, and J.-R. Sun, Chin. Phys. Soc. 16, 1817 (2007).ADSCrossRefGoogle Scholar
  6. 6.
    E. Z. Valiev, Phys. Met. Metallogr. 96, 121 (2003).Google Scholar
  7. 7.
    E. Z. Valiev and A. E. Teplykh, Crystallogr. Rep. 61, 89 (2016).ADSCrossRefGoogle Scholar
  8. 8.
    E. Z. Valiev and A. E. Teplykh, Phys. Met. Metallogr. 118, 21 (2017).ADSCrossRefGoogle Scholar
  9. 9.
    C. P. Bean and D. S. Rodbell, Phys. Rev. B 12, 104 (1962).CrossRefGoogle Scholar
  10. 10.
    S. V. Tyablikov, Methods in the Quantum Theory of Magnetism (2nd ed., Nauka, Moscow, 1975, Plenum, New York, 1967).CrossRefGoogle Scholar
  11. 11.
    K. P. Belov, A. K. Zvezdin, A. M. Kadomtseva, and R. Z. Levitin, Orientation Transitions in Rare-Earth Magnetics (Nauka, Moscow, 1979) [in Russian].Google Scholar
  12. 12.
    E. Z. Valiev, Phys. Met. Metallogr. 104, 8 (2007).ADSCrossRefGoogle Scholar
  13. 13.
    P. J. von Ranke, N. A. de Oliveira, B. P. Alho, et al., J. Phys.: Condens. Matter 21, 056004 (2009).ADSGoogle Scholar
  14. 14.
    S. A. Nikitin and A. M. Tishin, Gryogenics 31, 166 (1991).ADSCrossRefGoogle Scholar
  15. 15.
    J. Voiron, A. Berton, and I. Chaussy, Phys. Lett. A 50, 17 (1974).ADSCrossRefGoogle Scholar
  16. 16.
    A. E. Clark and E. Callen, J. Appl. Phys. 39, 5972 (1968).ADSCrossRefGoogle Scholar
  17. 17.
    A. S. Andreenko, K. P. Belov, S. A. Nikitin, and A. M. Tishin, Sov. Phys. Usp. 32, 649 (1989).ADSCrossRefGoogle Scholar

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© Pleiades Publishing, Inc. 2017

Authors and Affiliations

  1. 1.Institute of Metal Physics, Ural BranchRussian Academy of SciencesYekaterinburgRussia

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