High-[ital T][sub [ital c]] three-axis dc SQUID magnetometer for geophysical applications

Journal Article · Wed Nov 30 23:00:00 EST 1994 · Review of Scientific Instruments; (United States)

DOI:https://doi.org/10.1063/1.1145169· OSTI ID:6784002

Dantsker, E; Koelle, D; Miklich, A H; Nemeth, D T; Ludwig, F; Clarke, J ^[1]; Longo, J T; Vinetskiy, V ^[2]

---

1. Department of Physics, University of California, Berkeley, California 94720 (United States) Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)
2. Conductus, Inc., 969 West Maude Avenue, Sunnyvale, California 94086 (United States)

A prototype three-axis magnetometer has been developed, intended for geophysical applications, involving high-transition temperature dc superconducting quantum interference devices (SQUIDs). Each SQUID was fabricated from a thin film of YBa[sub 2]Cu[sub 3]O[sub 7[minus][ital x]] deposited on a SrTiO[sub 3] bicrystal to form two Josephson junctions, and was directly coupled to a single-turn pickup loop patterned in the same film. The three orthogonally mounted sensors were immersed in liquid nitrogen in a fiberglass Dewar and operated in separate flux-locked loops. In nominally zero ambient magnetic field, the best magnetic field resolution was 170 fT Hz[sup [minus]1/2] in the white noise, increasing to 225 fT Hz[sup [minus]1/2] at 1 Hz. The dynamic range was [plus minus]1.6[times]10[sup 6] Hz[sup 1/2] in the white noise, and the highest slew rate achieved was 1.6 mT s[sup [minus]1], at 900 Hz. The 3 dB point in the frequency response was about 90 kHz. The three channels were mutually orthogonal to about 1%. The three-axis magnetometer was also operated outside the laboratory in the presence of 60 Hz and radio-frequency noise.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6784002
• Journal Information: Review of Scientific Instruments; (United States), Journal Name: Review of Scientific Instruments; (United States) Vol. 65:12; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000 -- Geosciences
665412* -- Superconducting Devices-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
DESIGN
ELECTRONIC EQUIPMENT
EQUIPMENT
FABRICATION
FILMS
FLUXMETERS
GEOPHYSICAL SURVEYS
HIGH-TC SUPERCONDUCTORS
MAGNETIC SURVEYS
MAGNETOMETERS
MEASURING INSTRUMENTS
MICROWAVE EQUIPMENT
NOISE
OXIDES
OXYGEN COMPOUNDS
SENSITIVITY
SQUID DEVICES
SUPERCONDUCTING DEVICES
SUPERCONDUCTING FILMS
SUPERCONDUCTORS
SURVEYS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES