J. Phys. IV France 08 (1998) Pr3-237-Pr3-240
Readout of cryogenic particle detectors based on Nb/Al-AlOx/Al/Nb Josephson junctions using double relaxation oscillation SQUIDsA.W. Hamster, M.J. Van Duuren, G.C.S. Brons, J. Flokstra and H. Rogalla
Low Temperature Division, University of Twente, P. 0. Box 217, 7500 AE Enschede, The Netherlands
A Double Relaxation Oscillation SQUID has been operated in a wideband flux locked loop system. The first measurements show a bandwidth of 1 MHz and a slew rate of 2.5-105 Φ0/s in combination with a white flux noise level of 8 µΦ0/√Hz. his corresponds to an input current noise of our DROS based current sensor of 2.5 pA/√Hz and a slew rate of about 0.08 A/s. The white noise level is still somewhat larger than the typical value of 2 pA/√Hz obtained in a 100 kHz bandwidth. Further developments are necessary to increase the slew rate and the bandwidth to make a DROS suitable for current readout of particle detectors based on superconducting Nb/Al-AlOx/Al/Nb tunnel junctions.
© EDP Sciences 1998