Title :
A double dc SQUID based magnetometer
Author :
Maslennikov, Yu.V. ; Baljaev, A.V. ; Snigirev, O.V. ; Kaplunenko, O.V. ; Mezzena, R.
Author_Institution :
Cryoton Co. Ltd., Troitsk, Russia
fDate :
6/1/1995 12:00:00 AM
Abstract :
We have developed a double dc SQUID based magnetometer with a direct read-out circuit and measured its signal and noise characteristics. The inductances of the input SQUID and SQUID-preamplifier were 120 and 250 pH. Thin-film flux transformers on the separate substrates had an inductance of the order of 1 /spl mu/H each and a current sensitivity of 0.54 and 0.32 /spl mu/A//spl Phi//sub 0/ for the first and the second SQUIDs, respectively. The intrinsic energy resolution of the fabricated magnetometer for an optimal gain of 58 for the first stage was close to 1.6/spl times/10/sup -32/ J/Hz. The dynamic range and the slew rate were about 126 dB and 4/spl times/10/sup 4/ /spl Phi//sub 0//s.<>
Keywords :
SQUID magnetometers; superconducting device noise; current sensitivity; direct read-out circuit; double DC SQUID based magnetometer; dynamic range; energy resolution; gain; inductance; noise characteristics; preamplifier; slew rate; thin-film flux transformers; Circuit noise; Dynamic range; Energy resolution; Inductance; Magnetic circuits; Noise measurement; SQUID magnetometers; Substrates; Thin film circuits; Transformers;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
