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Rotating magnetocaloric effect in the ferromagnetic Weyl semi-metal Co$_{3}$Sn$_{2}$S$_{2}$

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 نشر من قبل Yogesh Singh
 تاريخ النشر 2019
  مجال البحث فيزياء
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The rotating magnetocaloric effect (RMCE) is a recent interest in magnetic refrigeration technique in which the cooling effect is attained by rotating the anisotropic magnetocaloric material from one orientation to the other in a fixed magnetic field. In this work, we report the anisotropic magnetocaloric properties of single crystals of the ferromagnetic Weyl semimetal Co$_{3}$Sn$_{2}$S$_{2}$ for magnetic field $Hparallel c$ axis and $Hparallel ab$ plane. We observed a significant (factor of $2$) difference between the magnetocaloric effect measured in both orientations. The rotating magnetocaloric effect has been extracted by taking the difference of the magnetic entropy change ($Delta S_{M}$) for fields applied in the two crystallographic orientations. In a scaling analysis of $Delta S_{M}$, the rescaled $Delta S_{M}(T,H)$ vs reduced temperature $theta$ curves collapse onto a single universal curve, indicating that the transition from paramagnetic to ferromagnetic phase at 174~K is a second order transition. Furthermore, using the power law dependence of $Delta S_{M}$ and relative cooling power RCP, the critical exponents $beta$ and $gamma$ are calculated, which are consistent with the recent critical behavior study on this compound cite{Yan2018}.


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