Title :
An HTS SQUID picovoltmeter with a flip-chip flux transformer
Author :
Blomgren, Jakob ; Eriksson, Thomas ; Winkler, Dag
Author_Institution :
Dept. of Microelectron. & Nanosci., Chalmers Univ. of Technol., Goteborg, Sweden
fDate :
3/1/2001 12:00:00 AM
Abstract :
An HTS SQUID picovoltmeter was constructed, which in two different configurations gave a voltage noise of en=3.2pV/√Hz and a current noise of in=310 pA/√Hz, and a voltage noise of en=75 pV/√Hz and a current noise of in=10 pA/√Hz, respectively. The low frequency noise was reduced to below 1 Hz using bias current reversal. The SQUID is coupled to the input coil via an intermediate flip-chip flux transformer. Measurements were performed to determine the input coil to SQUID mutual inductance for different input coil configurations
Keywords :
SQUIDs; flip-chip devices; high-temperature superconductors; superconducting device noise; superconducting transformers; voltmeters; HTS SQUID picovoltmeter; bias current reversal; current noise; flip-chip flux transformer; input coil; low-frequency noise; mutual inductance; voltage noise; Circuits; Coils; High temperature superconductors; Low-frequency noise; Magnetic noise; Resistors; SQUIDs; Superconducting device noise; Voltage; Voltmeters;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
