Large reversible magnetocaloric effect induced by metamagnetic transition in antiferromagnetic HoNiGa compound简

• Published in: 中国物理B：英文版 2016 (12), p.402-406
• Main Author: 王一旭 张虎 吴美玲 陶坤 李亚伟 颜天宝 龙克文 龙腾 庞铮 龙毅
• Format: Article
• Language: English
• ISSN: 1674-1056; 2058-3834

The magnetic properties and magnetocaloric effects（MCE） of Ho Ni Ga compound are investigated systematically.The Ho Ni Ga exhibits a weak antiferromagnetic（AFM） ground state below the Neel temperature TNof 10 K, and the AFM ordering could be converted into ferromagnetic（FM） ordering by external magnetic field. Moreover, the field-induced FM phase exhibits a high saturation magnetic moment and a large change of magnetization around the transition temperature,which then result in a large MCE. A large-?SM of 22.0 J/kg K and a high RC value of 279 J/kg without magnetic hysteresis are obtained for a magnetic field change of 5 T, which are comparable to or even larger than those of some other magnetic refrigerant materials in the same temperature range. Besides, the μ0H2/3dependence of |?SMpk| well follows the linear fitting according to the mean-field approximation, suggesting the nature of second-order FM–PM magnetic transition under high magnetic fields. The large reversible MCE induced by metamagnetic transition suggests that Ho Ni Ga compound could be a promising material for magnetic refrigeration in low temperature range.