超导量子干涉器件及其地磁探测应用进展

Superconducting quantum interference device and its application in geomagnetic detection

超导量子干涉器件(SQUID)是一种基于约瑟夫森隧道效应和磁通量子化效应的宏观量子化高灵敏度磁探测器,其中低温SQUID噪声可达fT/Hz^(1/2),在基础研究、材料科学、地球物理、天体物理、生命科学等领域都有非常广泛的应用。地球磁场可以近似为一个磁偶极子,但是地球磁场的微弱波动包含着丰富的信息,可以反映太阳风活动、地球电离层活动乃至地震先兆等信息,具有巨大的研究价值。本文系统回顾了国内外使用SQUID传感器进行地磁观测的研究进展,并讨论了中科院上海微系统所进行的SQUID系统观测地磁长时间波动及舒曼共振信号的探测结果。最后,对SQUID地磁观测的前景进行了展望。

Superconducting quantum interference device(SQUID)is a macro quantized high-sensitivity magnetic detector based on Josephson tunnel effect and flux quantization effect.The low-temperature squid noise can reach the order of fT/Hz^(1/2).It is widely used in basic research,material science,geophysics,astrophysics,life science and other fields.The earth’s magnetic field can be approximated as a magnetic dipole,but the weak fluctuation of the earth’s magnetic field contains rich information,which can reflect the solar wind activity,the earth’s ionospheric activity and even earthquake precursors,and has great research value.This paper systematically reviews the research progress of geomagnetic observation using SQUID sensor at home and abroad,and discusses the detection results of geomagnetic long-time fluctuation and Schumann resonance signal observed by SQUID system carried out by Shanghai Institute of Microsystem and Information Technology,Chinese Academy of Sciences.Finally,a brief prospect of SQUID-based geomagnetic observation is prospected.