扫描SQUID显微镜的研制及其在磁成像和无损检测中的应用  

A SCANNING SQUID MICROSCOPE AND ITS APPLICATIONS FOR MAGNETIC FIELD IMAGING AND NONDESTRUCTIVE EVALUATION

作　　者：张峰会[1] 丁红胜[1] 何豫生[1] 陈赓华[1] 韩士吉[1] 董世迎[1] 颜晓明[2] 杨乾声[1] 陈兆甲[1] 金铎[1] 

机构地区：[1]中国科学院物理研究所,北京100080 [2]中国科学院理化技术研究所,北京100080

出　　处：《低温物理学报》2004年第1期41-45,共5页Low Temperature Physical Letters

基　　金：国家自然科学基金 (批准号 :1982 70 0 1)资助课题~~

摘　　要：研制了两种用于检测室温样品的超导量子干涉器 (SQUID)扫描磁场显微镜 (以下简称扫描SQUID显微镜 ) ,一种使用常规低Tc(Nb)SQUID器件 ,另一种使用高温 (YBCO)SQUID器件 .SQUID安装在内杜瓦底部的冷指底端 ,外杜瓦底部有 6 0～ 75微米厚的白宝石窗口 ,被测样品处于室温状态位于窗口下 ,SQUID与被测样品之间的间距通过波纹管的伸缩进行调节 .常规低Tc(Nb)器件系统的空间分辨率优于 14 0 μm ,磁场灵敏度优于 3pT/Hz1 / 2 ,高温 (YBCO)器件系统的空间分辨率～ 5 0 0 μm ,磁场灵敏度～ 4 6pT/Hz1 / 2 .两者均能长时间稳定地工作在无屏蔽环境中 .利用两台扫描SQUID显微镜 ,进行了多种有应用价值的磁成像实验和无损检测研究 .We have built two scanning SQUID microscope for room temperature samples with LTS SQUID and HTS (YBCO) SQUID respectively. SQUIDs are mounted on the low end of the finger in Dewar. A thin sapphire window separates SQUIDs and samples. Samples stay in room temperature. The distance between SQUIDs and samples can be adjusted with a bellow. The LTS SQUID microscope has a field sensitivity superior to 3pT/Hz 1/2 and spatial resolution better than 140μm. The HTS SQUID system is of ～46pT/Hz 1/2 field sensitivity and ～500μm spatial resolution. Both microscopes can stably work for a long time in unshielded environment. We also have used them to do some interesting experiments for magnetic field imaging and nondestructive evaluation (NDE).

关 键 词：SQUID 显微镜 磁成像 无损检测 超导量子干涉器 空间分辨率 磁场灵敏度 移动控制系统 数据采集系统 

分 类 号：O441.5[理学—电磁学]