DC SQUID series array amplifiers with 120 MHz bandwidth

We report on the performance of dc SQUID (Superconducting Quantum Interference Device) series array amplifiers from dc to 500 MHz. The arrays consist of up to 100 dc SQUIDs, with varying degrees of intracoil damping; the flux focusing washer of each SQUID is electrically isolated from the SQUID loop...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on applied superconductivity 2001-03, Vol.11 (1), p.1251-1256
Main Authors: Huber, M.E., Neil, P.A., Benson, R.G., Burns, D.A., Corey, A.M., Flynn, C.S., Kitaygorodskaya, Y., Massihzadeh, O., Martinis, J.M., Hilton, G.C.
Format: Article
Language:English
Subjects:
Applied sciences
Bandwidth
Coils
Damping
Electronics
Exact sciences and technology
Interference
Radiofrequency amplifiers
Resonance
Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices
SQUIDs
Superconducting devices
Transfer functions
Voltage
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We report on the performance of dc SQUID (Superconducting Quantum Interference Device) series array amplifiers from dc to 500 MHz. The arrays consist of up to 100 dc SQUIDs, with varying degrees of intracoil damping; the flux focusing washer of each SQUID is electrically isolated from the SQUID loop (L/sub sq/=18 pH). Using an rf network analyzer, we have observed high-frequency resonances in the response at bias points corresponding to distortions in the dc transfer functions. Increasing distance between SQUIDs in the array reduces the distortions. Distortions are also more pronounced, and bandwidth reduced, in devices incorporating the flux-focusing washer into the SQUID body. With intracoil damping of 0.25 /spl Omega/ per turn on the input coil, the voltage-flux transfer characteristics of the isolated-washer design and 300 /spl mu/m center-to-center SQUID spacing are free of significant distortions, and the bandwidth is not degraded compared to undamped devices. The 100-SQUID array has 150 nH input inductance, 500 V/A transimpedance, 2.5 pA/ Hz equivalent input current noise at 4 K, and 120 MHz bandwidth.
ISSN:1051-8223
1558-2515
DOI:10.1109/77.919577