Title :
High temperature superconductor sensors for low field magnetometry
Author :
Niculescu, H. ; Gielisse, P.J.
Author_Institution :
Coll. of Eng., Florid A&M Univ., Tallahassee, FL, USA
fDate :
1/1/1992 12:00:00 AM
Abstract :
The nonlinear strong response of high-temperature superconductors immersed in alternating magnetic fields is employed for measurements of very weak DC fields. Even harmonics are generated due to a strong field dependence of the critical current in these materials. A second harmonic signal induced by magnetic flux threading a detection coil yielded a sensitivity to magnetic fields as low as several tenths of a picotesla. For the best bulk sensors, a minimum detectable flux density of 4×10-11 T was found for S/N (signal/noise)=1
Keywords :
coils; critical currents; high-temperature superconductors; magnetic field measurement; magnetometers; alternating magnetic fields; critical current; detection coil; harmonic signal; high-temperature superconductors; low field magnetometry; magnetic flux; minimum detectable flux density; nonlinear strong response; very weak DC fields; Critical current; High temperature superconductors; Magnetic field measurement; Magnetic flux; Magnetic materials; Magnetic sensors; Superconducting coils; Superconducting magnets; Superconducting materials; Temperature sensors;
Journal_Title :
Magnetics, IEEE Transactions on
