Planar microwave biased radio frequency SQUIDs with a cryogenic preamplifier
- 7 September 1992
- journal article
- Published by AIP Publishing in Applied Physics Letters
- Vol. 61 (10) , 1231-1233
- https://doi.org/10.1063/1.107604
Abstract
We report on the design and performance of a planar microwave rf-SQUID readout by a cryogenic preamplifier. The SQUID-sensor consists of a planar half-wavelength microstrip resonator, into which the SQUID-loop is integrated. The pump frequency is 1.7 GHz. The cryogenic preamplifier employs a microwave high electron mobility transistor (HEMT), located close to the SQUID sensor. Measurements of the flux noise and the fractional step rise parameter were carried out in the temperature range between 4.2 and 1.5 K. In an open loop white flux noise values of 2×10−6 Φ0/√Hz were obtained at 4.2 K.Keywords
This publication has 4 references indexed in Scilit:
- Cryogenic GaAs-FET amplifiers for SQUIDSJournal of Low Temperature Physics, 1979
- Performance factors in rf SQUIDs--High frequency limitIEEE Transactions on Magnetics, 1977
- Noise in the rf SQUIDJournal of Low Temperature Physics, 1975
- Noise in the superconducting quantum flux detectorJournal of Applied Physics, 1973