Development of high Tc superconductor SQUID-based magnetometer

• Published in: Cryogenics (Guildford) 1993-06, Vol.33 (6), p.632-636
• Main Authors: Konotop, D.A., Khvostov, S.S., Timofeev, V.P., Shnyrkov, V.I., Tsoi, G.M.
• Format: Article
• Language: English
• Subjects: Exact sciences and technology; high Tc superconductors; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Magnetic components, instruments and techniques; magnetometers; Physics; SQUIDs
• ISSN: 0011-2275; 1879-2235
• DOI: 10.1016/0011-2275(93)90121-4

The present paper describes the design and development of a liquid nitrogen-cooled RF SQUID magnetometer made of high T c superconductor (HTS) Y-Ba-Cu-O ceramics. The cryogenic module, glass-reinforced plastic cryostat and HTS SQUID ensure stable performance at the sensitivity level of 2 × 10 −13 − 4 × 10 −13 T Hz sol−1 2 over a period of one year. The service period of the system after a single nitrogen filling is about 10–12 days. A differential HTS magnetometer design is also described. The magnetic noise spectral density of this magnetometer was measured in a shielded room consisting of two layers of commercially pure aluminium. It was shown that the use of this differential magnetometer decreased the contribution of variations in the environmental magnetic field to the output signal by 100 times. Magnetocardiographic traces were obtained.