Herein, we report a potential solid-state magnetic cooling candidate gadolinium borotungstate Gd₃BWO₉ that shows an exceptionally large magnetocaloric effect. Experimental investigations on the crystal structure, bulk magnetic and heat capacity properties down to 300 mK were performed, along with the theoretical analysis of the electronic and magnetic features through density functional theory (DFT) and mean-field approach. The isothermal magnetic entropy change was identified to be 454 mJ K⁻¹ cc⁻¹ for a field variation of 9 T at 2.4 K, which are among the highest records ever reported. The substantial magnetocaloric effect makes Gd₃BWO₉ a strong alternative for cryogenic refrigeration at ultra-low temperatures and in the magnetic gas liquefaction.

中文翻译：

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硼钨酸G Gd3BWO9中的大磁热效应

在此，我们报告了潜在的固态磁冷却候选物硼钨酸G Gd ₃ BWO ₉，其表现出极大的磁热效应。通过密度泛函理论（DFT）和平均场方法，对晶体结构，体磁和热容量特性（低至300 mK）进行了实验研究，并对电子和磁性特征进行了理论分析。对于在2.4 K下9 T的磁场变化，确定的等温磁熵变为454 mJ K ^-1 cc ^-1，这是有史以来最高记录。显着的磁热效应使Gd ₃ BWO ₉ 在超低温和磁性气体液化中进行低温制冷的强大替代方案。