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arXiv · 1812.05798

Anisotropic magnetic properties and giant rotating magnetocaloric effect in double-perovskite Tb2CoMnO6

J. Y. Moon·M. K. Kim·D. G. Oh·J. H. Kim·H. J. Shin·Y. J. Choi·N. Lee
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Abstract

We investigated the anisotropy of the magnetic and magnetocaloric properties of singlecrystalline double perovskite Tb2CoMnO6, which crystallizes in a monoclinic P21/n structure. Due to dissimilar magnetic anisotropy, the ferromagnetic order of the Co2+ and Mn4+ moments emerges along the c-axis at TC = 100 K, and the larger Tb3+ moments align perpendicular to the c-axis, below TTb = 15 K. The intricate temperature development of the metamagnetism along the c-axis results in a large negative change in the magnetic entropy at low temperature. On the other hand, the larger but almost reversible magnetization, perpendicular to the c-axis, results in a small and positive entropy change. This highly anisotropic magnetocaloric effect (MCE) leads to a giant rotational MCE, estimated to be 20.8 J/kg K. Our findings, based on the magnetic anisotropy in Tb2CoMnO6, enrich fundamental and applied research on magnetic materials, considering the distinct magnetic characteristics of double perovskites.

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J. Y. Moon, M. K. Kim, D. G. Oh, J. H. Kim, H. J. Shin, Y. J. Choi, N. Lee. 2018-12-14. Anisotropic magnetic properties and giant rotating magnetocaloric effect in double-perovskite Tb2CoMnO6. https://doi.org/10.1103/physrevb.98.174424

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