稀土-镓化合物的多重磁相变及磁熵变  

The multiple magnetic transitions and magnetic entropy change of RGa compounds

作　　者：郑新奇[1] 许家旺 杨淑娴 奚磊 张虎[1] 王守国 沈保根 ZHENG XinQi;XU JiaWang;YANG ShuXian;XI Lei;ZHANG Hu;WANG ShouGuo;SHEN BaoGen(Beijing Advanced Innovation Center for Materials Genome Engineering,School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China;Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;Institute of Rare Earths,Chinese Academy of Sciences,Ganzhou 341000,China)

机构地区：[1]北京科技大学材料科学与工程学院,北京材料基因工程高精尖创新中心,北京100083 [2]中国科学院物理研究所,北京凝聚态物理国家研究中心,北京100190 [3]中国科学院大学物理科学学院,北京100049 [4]中国科学院稀土研究院,赣州341000

出　　处：《中国科学：物理学、力学、天文学》2021年第6期64-78,共15页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家重点基础研究发展计划(编号:2017YFB0702701,2019YFB2005800,2017YFA0206300);国家自然科学基金(编号:51871019,11674008,51590880,51625101,51971026,51961145305)资助项目。

摘　　要：中低温区磁制冷材料可用于液氧、液氮、液氢、液氦等资源的获得因而引起人们的关注,探索并获得具有大磁熵变、宽制冷温跨、大制冷能力以及大绝热温变的磁制冷材料是科研人员持续不断的追求.稀土-镓是一类磁相变信息丰富的稀土基合金化合物,本文综述了镨-镓、钕-镓、钐-镓、钆-镓、铽-镓、镝-镓、钬-镓、铒-镓、铥-镓以及钆铒互替代样品的低温有序-有序磁相变、高温有序-无序磁相变以及磁熵变结果.稀土-镓化合物的低温有序-有序磁相变类型包括自旋重取向相变、铁磁-调制反铁磁相变以及锥角铁磁-锥角铁磁相变,其磁熵变曲线呈现多个峰,这一特点为宽制冷温跨材料的设计提供了思路.本文还分析了稀土-镓化合物磁相变和磁熵变的特点,阐述了它们的依赖关系和背后的物理机理,展望了未来可能的研究课题.Magnetic refrigerant materials working at middle and low temperature range have drawn much attention because they can be used for gas liquefaction such as oxygen, nitrogen, hydrogen and helium. It is continuous goal for researchers to explore and obtain magnetic refrigerant materials with large magnetic entropy change, wide refrigerant temperature span,high refrigeration capacity and large adiabatic temperature change. RGa family is a kind of rare earth based intermetallic compounds with abundant magnetic transitions. This paper reviews the results of low-temperature order-order magnetic transition, high-temperature order-disorder magnetic transition and magnetic entropy change for PrGa, NdGa, Sm Ga,GdGa, TbGa, DyGa, HoGa, ErGa, TmGa and Er-1-xGdxGa compounds. The low-temperature order-order magnetic transition includes spin reorientation transition, ferromagnetic to modulated antiferromagnetic transition and coneferromagnetic to cone-ferromagnetic transition. There are several peaks on the magnetic entropy change curves which provide ideas for designing magnetic refrigerant materials with large temperature span. The characteristics of magnetic transitions and magnetic entropy change for RGa compounds are analyzed, the dependency relationship together with related physical mechanism are expounded and the possible research interests in the future are discussed.

关 键 词：自旋重取向 磁相变 磁熵变 磁热效应 

分 类 号：O469[理学—凝聚态物理]