用于微尺度磁体磁化测量的高温超导微超导量子干涉器件磁力计

High temperature superconductor micro-superconducting-quantum-interference-device magnetometer for magnetization measurement of a microscale magnet.

作者信息

Takeda Keiji, Mori Hatsumi, Yamaguchi Akira, Ishimoto Hidehiko, Nakamura Takayoshi, Kuriki Shinya, Hozumi Toshiya, Ohkoshi Shin-ichi

机构信息

Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba 277-8581, Japan.

出版信息

Rev Sci Instrum. 2008 Mar;79(3):033909. doi: 10.1063/1.2894332.

DOI:10.1063/1.2894332

PMID:18377027

Abstract

We have developed a high temperature superconductor (HTS) micrometer-sized dc superconducting quantum interference device (SQUID) magnetometer for high field and high temperature operation. It was fabricated from YBa2Cu3O7-delta of 92 nm in thickness with photolithography techniques to have a hole of 4x9 microm2 and 2 microm wide grain boundary Josephson junctions. Combined with a three dimensional magnetic field coil system, the modulation patterns of critical current Ic were observed for three different field directions. They were successfully used to measure the magnetic properties of a molecular ferrimagnetic microcrystal (23x17x13 microm3), [Mn2(H2O)2(CH3COO)][W(CN)8]2H2O. The magnetization curve was obtained in magnetic field up to 0.12 T between 30 and 70 K. This is the first to measure the anisotropy of hysteresis curve in the field above 0.1 T with an accuracy of 10(-12) J T(-1) (10(-9) emu) with a HTS micro-SQUID magnetometer.

摘要

我们已开发出一种用于高场和高温运行的高温超导（HTS）微米级直流超导量子干涉器件（SQUID）磁力计。它由厚度为92纳米的YBa2Cu3O7-δ制成，采用光刻技术制作，有一个4×9微米2的孔和2微米宽的晶界约瑟夫森结。结合三维磁场线圈系统，观察了三种不同场方向下临界电流Ic的调制模式。它们成功地用于测量分子亚铁磁性微晶（23×17×13微米3）[Mn2(H2O)2(CH3COO)][W(CN)8]2H2O的磁性。在30至70 K之间，在高达0.12 T的磁场中获得了磁化曲线。这是首次使用高温超导微型SQUID磁力计在高于0.1 T的磁场中以10（-12）J T（-1）（10（-9）emu）的精度测量磁滞曲线的各向异性。