High sensitive magnetometers and gradiometers based on dc SQUIDs with flux focuser

Conference · Thu Feb 28 23:00:00 EST 1991 · IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers); (United States)

OSTI ID:6089215

Matlashov, A N; Koshelets, V P; Kalashnikov, P U; Zhuravlev, Y E; Slobodchikov, V Y; Kovtonyuk, S A; Filippenki, L V ^[1]

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1. Institute of Radio Engineering and Electronics, USSR Academy of Sciences, Marx Avenue 18, Moscow GSP-3 (SU)

This paper reports on high sensitive dc SQUID magnetometers and gradiometers with flux focusers instead of traditional coupling coils designed and experimentally tested. All refractory material DC SQUIDs with shunted Nb---AlO{sub x}---Nb tunnel junctions were used. The outer dimension of the square washer electrode was 2.5 mm, the inner one was 70{mu}m. A wide superconducting washer concentrates the magnetic flux by twenty times and the flux sensitivity about 20 nT/{phi}{sub 0} can be realized without any input coil. The application of the additional 14 mm diameter flux focuser has increased the flux concentration by four times more. As a result the magnetic field resolution 10 fT/square root Hz has been achieved; this figure corresponds to the flux resolution about 2 {center dot} 10{sup {minus}6}{phi}{sub 0}/square root Hz. Connecting the additional flux focuser to the placed apart compensation coils one can create gradiometers of both the first and higher orders.

• OSTI ID: 6089215
• Report Number(s): CONF-900944--
• Journal Information: IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers); (United States), Journal Name: IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers); (United States) Vol. 27:2; ISSN IEMGA; ISSN 0018-9464
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420500 -- Engineering-- Materials Testing
440800 -- Miscellaneous Instrumentation-- (1990-)
47 OTHER INSTRUMENTATION
665412* -- Superconducting Devices-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
BEAM OPTICS
CALCULATION METHODS
CHALCOGENIDES
DESIGN
EDDY CURRENT TESTING
ELECTROMAGNETIC PULSES
ELECTROMAGNETIC RADIATION
ELECTROMAGNETIC TESTING
ELECTRONIC EQUIPMENT
ELEMENTS
EQUIPMENT
FABRICATION
FLUXMETERS
FOCUSING
JUNCTIONS
MAGNETIC FLUX
MAGNETOMETERS
MATERIALS TESTING
MEASURING INSTRUMENTS
METALS
MICROWAVE EQUIPMENT
MULTI-CHANNEL ANALYZERS
NIOBIUM
NONDESTRUCTIVE TESTING
OXIDES
OXYGEN COMPOUNDS
PULSE ANALYZERS
PULSES
RADIATIONS
SENSITIVITY
SQUID DEVICES
SUPERCONDUCTING DEVICES
SUPERCONDUCTING JUNCTIONS
TESTING
TRANSITION ELEMENTS
TUNNEL EFFECT