La_(0.67)Sr_(0.33)Mn_(0.9)Cr_(0.1)O_3的巨磁熵效应  

Colossal Magnetic Entropy Effect of La_(0.67)Sr_(0.33)Mn_(0.9)Cr_(0.1)O_3

作　　者：彭振生[1] 

机构地区：[1]宿州师范专科学校物理系

出　　处：《稀有金属》2004年第2期322-325,共4页Chinese Journal of Rare Metals

基　　金：国家自然科学基金重点资助项目 (1993 40 0 3 );国家重点基础研究发展规划项目 (0 0 1CB610 60 4)

摘　　要：通过测量不同温度下的M T和M H曲线 ,对超大磁阻材料La0 .6 7Sr0 .33Mn0 .9Cr0 .1 O3的巨磁熵进行了研究 ,发现伴随铁磁 顺磁相变有一个大的磁熵变化 ;在 3 3 7K左右出现了一个磁熵肩峰 ,并随磁场的增大而愈加明显。由于磁熵肩峰的出现 ,磁熵变的峰被拉宽 ,从而有利于采用ERICSSON循环的磁制冷。这个结果表明La0 .6 7Sr0 .33Mn0 .9Cr0 .1 O3可以作为磁制冷技术工作物质。The colossal magnetic entropy of the gigantic magnetoresistance material La 0.67Sr 0.33Mn 0.9Cr 0.1O 3 was studied by measuring M-T and M-H curves under different temperatures. The results show that there is a great change of magnetic entropy along with ferromagnetism-paramagnetism (FM-PM) transition. A shoulder peak appears at ～337 K, more obvious with the increase of magnetic field. With the appearance of shoulder peak of magnetic entropy , the peak of magnetic entropy change is enlarged, thus it is good to adopt the magnetic refrigeration of Ericsson circulation. This result shows that La 0.67Sr 0.33Mn 0.9Cr 0.1O 3 can be used as the material of magnetic refrigeration technology.

关 键 词：磁制冷材料 巨磁熵效应 磁熵肩峰 

分 类 号：TM273[一般工业技术—材料科学与工程]