Development of a high-speed and high-sensitive optical output system for high-performance magnetic devices

研制了一种高速、高灵敏度的激光扫描磁光显微镜，作为磁性器件的诊断仪器和光学输出接口。利用该系统，我们成功地对超导器件中的磁场分布进行了快速定量成像，灵敏度达到~100μT，并成功地探测了超导回路中产生的单个磁通量子。此外，我们还成功地利用交流调制技术，在~ 1 mA的小电流作用下，对超导带线周围的弱磁场分布进行了成像。

A high-speed and high-sensitive laser scanning magneto-optical microscope has been developed as a diagnostic apparatus and an optical output interface for magnetic devices. Using this system we have succeeded in the fast and quantitative imaging of a magnetic field distribution in superconductor devices with a sensitivity of ～100μT, and also succeeded in the detection of a single flux quantum generated in a superconducting loop. Furthermore, we succeeded in the imaging of weak magnetic field distribution around superconducting strip-line applied with a current as small as ～1mA by means of ac-modulation technique.