High-sensitive scanning laser magneto-optical imaging system

作者：Murakami Hironaru^*; Tonouchi Masayoshi

来源：Review of Scientific Instruments, 2010, 81(1): 013701.

DOI：10.1063/1.3276710

• Faraday effect
• laser beam applications
• magnetic field measurement
• magneto-optical devices
• optical microscopes

A high-sensitive scanning laser magneto-optical (MO) imaging system has been developed. The system is mainly composed of a laser source, galvano meters, and a high-sensitive differential optical-detector. Preliminary evaluation of system performance by using a Faraday indicator with a Faraday rotation coefficient of 3.47x10(-5) rad/mu m Oe shows a magnetic sensitivity of about 5 mu T, without any need for accumulation or averaging processing. Using the developed MO system we have succeeded in the fast and quantitative imaging of a rotationally symmetric magnetic field distribution around an YBa(2)Cu(3)O(7-delta) (YBCO) strip line applied with dc-biased current, and also succeeded in the detection of quantized fine signals corresponding to magnetic flux quantum generation in a superconducting loop of an YBCO Josephson vortex flow transistor. Thus, the developed system enables us not only to do fast imaging and local signal detection but also to directly evaluate both the strength and direction of a magnetic signal.

• 出版日期2010-1