Title :
Low noise HTS dc-SQUID flip-chip magnetometers and gradiometers
Author :
Faley, M.I. ; Poppe, U. ; Urban, K. ; Paulson, D.N. ; Starr, T.N. ; Fagaly, R.L.
Author_Institution :
Inst. fur Festkorperforschung, Forschungszentrum Julich GmbH, Germany
fDate :
3/1/2001 12:00:00 AM
Abstract :
We have fabricated HTS dc-SQUID flip-chip sensors with a large area multilayer flux transformers. Different layouts of the flux transformers provide a large variety of magnetometers and planar gradiometers. For the magnetometers a resolution ~6 fT/√Hz and the planar gradiometers a resolution of about ~30 fT/cm.√Hz were routinely obtained at 77 K. The noise was nearly white down to frequencies of few Hz. The sensors were vacuum-tight encapsulated together with a heater and a feedback coil. This makes the handling of the sensors more reproducible and convenient. Production of the magnetometers and gradiometers in small series was proven
Keywords :
SQUID magnetometers; flip-chip devices; high-temperature superconductors; superconducting device noise; superconducting transformers; white noise; 77 K; HTS DC-SQUID flip-chip sensor; magnetometer; multilayer flux transformer; planar gradiometer; vacuum encapsulation; white noise; Coils; Feedback; Frequency; High temperature superconductors; Magnetic multilayers; Magnetic sensors; Magnetometers; Thermal sensors; Transformers; White noise;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
