Title :
DC-SQUID electronics based on adaptive positive feedback: experiments
Author :
Seppa, Heikki ; Ahonen, A. ; Knuutila, J. ; Simola, J. ; Volkman, V.
Author_Institution :
VTT, Tech. Res. Centre of Finland, Espoo, Finland
fDate :
3/1/1991 12:00:00 AM
Abstract :
It is shown that DC-SQUID read-out electronics can be realized utilizing positive feedback without deteriorating the SQUID noise performance. The required gain rise is achieved by interconnecting the SQUID output and a flux modulation coil via a cooled FET acting as a voltage-controlled resistor; different SQUIDs with different types of FETs have been studied experimentally. Possible ways of adaptively controlling the feedback gain produced by the positive feedback are briefly discussed
Keywords :
SQUIDs; electron device noise; feedback; DC-SQUID electronics; adaptive positive feedback; cooled FET; feedback gain; flux modulation coil; gain rise; noise performance; read-out electronics; voltage-controlled resistor; Coils; FETs; Feedback; Gallium arsenide; Preamplifiers; Resistors; SQUIDs; Temperature; Thermal resistance; Voltage;
Journal_Title :
Magnetics, IEEE Transactions on
