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arXiv · 2405.20714

Large low-field magnetocaloric response in a ferromagnetic gadolinium orthophosphate

Ziyu W. Yang·Jie Zhang·Maocai Pi·Xubin Ye·Chenxu Kang·Xiaoliang Weng·Wei Tang·Hongzhi Cui·Yu-Jia Zeng·Youwen Long
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Abstract

Bulk magnetic and thermodynamic measurements, along with mean-field calculations, were conducted on the ferromagnetic K3Gd5(PO4)6 powders. No magnetic ordering was observed until 2 K, while the application of an external field B > 1 T resulted in the splitting of the Gd3+ ground state multiplet and induced a non-cooperative Schottky effect. The average nearest-neighbor exchange strength |J1/kB| is determined to be 0.017 K, which leads to a remarkably large low field magnetic entropy change {\Delta}Sm = 36.2 J kg-1 K-1 under applied field change B = 2 T at temperature T = 2 K, as well as a maximum adiabatic temperature change Tad = 10.9 K. We contend that ferromagnetic gadolinium orthophosphates serve as a promising reservoir for exploring advanced magnetic refrigerants applicable under low magnetic fields.

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Ziyu W. Yang, Jie Zhang, Maocai Pi, Xubin Ye, Chenxu Kang, Xiaoliang Weng, Wei Tang, Hongzhi Cui, Yu-Jia Zeng, Youwen Long. 2024-05-31. Large low-field magnetocaloric response in a ferromagnetic gadolinium orthophosphate. https://arxiv.org/abs/2405.20714

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