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arXiv · 1311.4161

Giant magnetocaloric effect in magnetoelectric Eu1-xBaxTiO3

Km Rubi·Pawan Kumar·D. V. Maheswar Repaka·Ruofan Chen·Jian-Sheng Wang·R. Mahendiran
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Abstract

We report the magnetic entropy change (Delta Sm) in magnetoelectric Eu1-xBaxTiO3 for x = 0.1- 0.9. We find - delta Sm = 11 (40) J/kg.K in x = 0.1 for a field change of 1 (5) Tesla respectively, which is the largest value among all Eu-based oxides. Delta Sm arises from the field-induced suppression of the spin entropy of Eu2+:4f7 localized moments. While -delta Sm decreases with increasing x, -DeltaSm = 6.58 J/kg.K observed in the high spin diluted composition x = 0.9 is larger than that in many manganites. Our results indicate that these magnetoelectrics are potential candidates for cryogenic magnetic refrigeration.

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Km Rubi, Pawan Kumar, D. V. Maheswar Repaka, Ruofan Chen, Jian-Sheng Wang, R. Mahendiran. 2013-11-17. Giant magnetocaloric effect in magnetoelectric Eu1-xBaxTiO3. https://doi.org/10.1063/1.4862981

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