Large Barocaloric Effect with High Pressure-Driving Efficiency in a Hexagonal MnNi0.77Fe0.23Ge Alloy  

作　　者：Qingqi Zeng Jianlei Shen Enke Liu Xuekui Xi Wenhong Wang Guangheng Wu Xixiang Zhang 曾庆祺;申建雷;刘恩克;郗学奎;王文洪;吴光恒;张西祥(Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China;Songshan Lake Materials Laboratory,Dongguan 523808,China;Physical Science and Engineering Division(PSE),King Abdullah University of Science and Technology(KAUST),Thuwal 23955-6900,Saudi Arabia)

机构地区：[1]Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]Songshan Lake Materials Laboratory,Dongguan 523808,China [4]Physical Science and Engineering Division(PSE),King Abdullah University of Science and Technology(KAUST),Thuwal 23955-6900,Saudi Arabia

出　　处：《Chinese Physics Letters》2020年第7期47-50,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China(Grant No.51722106);the National Key R&D Program of China(Grant No.2019YFA0704904);Users with Excellence Program of Hefei Science Center CAS(Grant No.2019HSC-UE009);Fujian Institute of Innovation,Chinese Academy of Sciences。

摘　　要：The hydrostatic pressure is expected to be an effective knob to tune the magnetostructural phase transitions of hexagonal MM’X alloys(M and M’denote transition metals and X represents main group elements).We perform magnetization measurements under hydrostatic pressure on an MM’X martensitic MnNi0.77Fe0.23Ge alloy.The magnetostructural transition temperature can be efficiently tuned to lower temperatures by applying moderate pressures,with a giant shift rate of-151 K/GPa.A temperature span of 30 K is obtained under the pressure,within which a large magnetic entropy change of-23 J·kg-1K-1 in a field change of 5 T is induced by the mechanical energy gain due to the large volume change.Meanwhile,a decoupling of structural and magnetic transitions is observed at low temperatures when the martensitic transition temperature is lower than the Curie temperature.These results show a multi-parameter tunable caloric effect that benefits the solid-state cooling.

关 键 词：temperature. TRANSITIONS martensitic 

分 类 号：O482.5[理学—固体物理] TG132.2[理学—物理]