Bi基超导体研磨非晶化的EXAFS研究  

EXAFS STUDY ON GRINDING NONCRYSTALLIZATION OF Bi-BASED SUPERCONDUCTOR

作　　者：孙红茂 赵贵文[1] 霍登伟[1] 周贵恩[1] 

机构地区：[1]中国科技大学应用化学系,中国科技大学结构成份分析中心

出　　处：《低温物理学报》1994年第1期43-47,共5页Low Temperature Physical Letters

基　　金：国家自然科学基金;国家博士点基金

摘　　要：本文研究了研磨对Ｂｉ－Ｓｒ－Ｃａ－Ｃｕ－Ｏ超导体２２１２相的影响．发现干法研磨导致晶相向非晶态的转变．而加入有机溶剂的湿法研磨对晶体结构破坏很小．对两种不同研磨条件下，Ｃｕ原子和Ｂｉ原子局域结构的ＥＸＡＦＳ研究，发现Ｂｉ原子第一配位层配位状态基本无变化，第二、第三层原子配位距离相同．但无序度显著增大，而Ｃｕ原子第一配位层中两种不同配位环境氧原子的无序度有不同程度的增大．由此推断，研磨所导致的非晶态是由于层与层之间的微小滑移而导致的无规则网络结构．Abstract Grinding effects on 2212-phase of Bi-Sr-Ca-Cu-O superconductor have been studied. The change from crystal into noncrystal occured by grindins the superconductor in air. The mechanism of non-crystallization has been researched by investigating the local structure of Cu and Bi atoms. It has shown that the coordination status of the first shell of Bi atom bears little change after grinding, while from the second shell, it becomes disordered; Disorder also occurs for the two different kinds of oxygenatom around copper. It is supposed that the non-crystallization is the result from slight slide between layers of the structure of the superconductor.

关 键 词：超导体 铋系 研磨 非晶态 

分 类 号：O511.1[理学—低温物理]