Title :
High-TC SQUID magnetometers for low noise measurements of magnetocardiograms
Author :
Kim, I.S. ; Yu, K.K. ; Lee, Y.H. ; Kim, K.W. ; Park, Y.K.
Author_Institution :
Korea Res. Inst. of Stand. & Sci., Taejon, South Korea
fDate :
6/1/2005 12:00:00 AM
Abstract :
YBCO dc superconducting quantum interference device (SQUID) magnetometers based on bicrystal junctions have been fabricated for magnetocardiograph measurements. The pickup coil of the device was designed employing 16 parallel loops with 50-μm-wide lines. Noise performance was improved by applying a modification in the coupling line between pickup loop and SQUID washer. We could obtain optimized SQUID magnetometer design having magnetic field noise of about 38 fT/Hz12/ at 1 Hz and about 20 fT/Hz12/ at 100 Hz with an 1/f corner frequency of 2 Hz, measured inside a magnetically-shielded room. Demonstration of magnetocardiograph measurements showed quite promising results with high signal-to-noise ratio of 82 with a moderate magnetic shielding.
Keywords :
SQUID magnetometers; barium compounds; magnetocardiography; yttrium compounds; 1 Hz; 2 Hz; YBCO dc superconducting quantum interference device magnetometers; YBa2Cu3O7; bicrystal junctions; high-TC SQUID magnetometers; low noise measurements; magnetic field noise; magnetocardiograms; magnetocardiograph measurements; Josephson junctions; Magnetic field measurement; Magnetic noise; Magnetic shielding; SQUID magnetometers; Superconducting coils; Superconducting device noise; Superconducting devices; Superconducting magnets; Yttrium barium copper oxide; High-; SQUID; magnetocardiograph;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2005.849985
