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arXiv · 1012.2102

The magnetocaloric and barocaloric effects in Gd5Si2Ge2 compound

Junding Zou
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Abstract

The caloric effect in Gd5Si2Ge2 compound is studied experimentally and theoretically. The first-order phase transition is sensitive to both magnetic field and pressure. It indicates that the influences of magnetic field and pressure on the phase transition are virtually equivalent. Moreover, the theoretical analyses reveal that the total entropy change is almost definite at a certain Curie temperature whether the applied external field is magnetic field or pressure. On the basis of theoretical analyses, the entropy change simultaneously induced by magnetic field and hydrostatic pressure can be obtained experimentally. As for Gd5Si2Ge2 compound, the entropy change curve is broadened dramatically, and the refrigerant capacity is improved from 284.7 to 447.0 J/kg. Additionally, the required magnetic field in magnetic refrigeration technique may be reduced by the application of hydrostatic pressure.

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Junding Zou. 2011-10-10. The magnetocaloric and barocaloric effects in Gd5Si2Ge2 compound. https://doi.org/10.1088/1674-1056%2F21%2F3%2F037503

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