An integrated DC SQUID gradiometer for biomagnetic application

Conference · Wed Mar 01 00:00:00 EST 1989 · IEEE Trans. Magn.; (United States)

OSTI ID:5920109

Koyanagi, M; Kasai, N; Nakanishi, M; Kosaka, S; Kado, H; Higuchi, M

The first order off-diagonal gradiometer was fabricated and tested. The gradiometer consisted of two field pickup coils, and a planar type DC SQUID with two superconducting loops connected in parallel, two multi-turn input coils and a modulation-feedback coil. The size of the pickup coils was 6x6 mm/sup 2/ with a base line of 8 mm. The overall size of the gradiometer was 15x7.5 mm/sup 2/. The resolution of the magnetic field gradient of the gradiometer increased from 11 to 1.8 pT/m..sqrt..Hz, corresponding to frequencies from 1 Hz to 600 hz. The resolution became nearly white in a frequency range above 600 Hz. The intrinsic balance of the gradiometer was better than 1000 ppm for the field perpendicular to its plane.

• Research Organization: Electrotechnical Lab., Umezono 1-1-4, Tsukuba-shi, Ibaraki (JP); Seiko Instr. Inc. (US); Institute of Applied Physics, Univ. of Tsukuba (JP)
• OSTI ID: 5920109
• Report Number(s): CONF-880812-
• Journal Information: IEEE Trans. Magn.; (United States), Vol. 25:2; Conference: Applied superconductivity conference, San Francisco, CA, USA, 21 Aug 1988
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
SQUID DEVICES
DESIGN
SUPERCONDUCTING COILS
FABRICATION
FEEDBACK
INTEGRATED CIRCUITS
MAGNETIC FIELDS
MAGNETOMETERS
MEASURING METHODS
USES
ELECTRONIC CIRCUITS
ELECTRONIC EQUIPMENT
EQUIPMENT
FLUXMETERS
MEASURING INSTRUMENTS
MICROELECTRONIC CIRCUITS
MICROWAVE EQUIPMENT
SUPERCONDUCTING DEVICES
420201* - Engineering- Cryogenic Equipment & Devices