高压热处理La_2CuO_(4.03)的超导电性和相分离  

PHASE SEPARATION IN La 2CuO 4.03 AFTER HIGH PRESSURE HEAT TREATMENT

作　　者：曹大呼[1] 陈玲[1] 姚玉书[1] 李克强[1] 倪咏明[1] 董成[1] 吴非[1] 陈红[1] 贾顺连[1] 赵忠贤[1] 

机构地区：[1]中国科学院物理研究所国家超导实验室,北京100080

出　　处：《低温物理学报》1999年第5期393-396,共4页Low Temperature Physical Letters

摘　　要：电化学恒流法增氧获得的超导临界转变温度约３０Ｋ，柰尔温度约２４５Ｋ 的反铁磁超导共存Ｌａ２ＣｕＯ４ ．０３ 超导体，在６ＧＰａ，４５０ ℃下热处理半小时，淬火至室温后，样品晶胞体积比常规样品被压缩约１ ％ ，正交畸变明显减小．超导临界转变温度提高到４０Ｋ左右．高场直流磁化率测量表明样品相分离后反铁磁相的柰尔温度明显提高，但又显示出富氧的特征．A superconductor with T c of 30K and T N of 245K was prepared by electrochemical method. The sample was in the miscibility gap for AF and SC separation. Heat treated under high pressure 6GPa at 450℃ for half an hour, we obtained the mixture of non superconductive phase of La 2CuO 4+ δ 1 and a separated phase of La 2CuO 4+ δ 2 . After HP annealing, the unit cell volume is compressed by 1% and T c is risen up to 40K. By measurements of high field magnetisation, it is found that T N increased. This phenomenon was explained according to the phase separation model.

关 键 词：超导电性 相分离 LCO 超导体 高压热处理 

分 类 号：TM262.014[一般工业技术—材料科学与工程] O511[电气工程—电工理论与新技术]