Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

SQUID Operational Amplifier

Published

Author(s)

Kent D. Irwin, Martin Huber

Abstract

The nonlinear response of Superconducting Quantum Interface Devices (SQUIDs) has limited their usefulness. We propose the SQUID Operational Amplifier, which consists of several stages of SQUIDs with high open-loop current gain. When connected in a negative-feedback configuration by passing some of the output current through a feedback coil connected to the first stage, the response is linearized. An analog of the semiconductor op-amp, the SQUID op-amp can be used in superconducting equivalents of op-amp circuits such as current amplifiers, current-to-voltage converters, differentiators, and integrators. We present experimental results with a x 10 current amplifier as well as a 750 ohm} current-to-voltage amplifier which can couple directly to a room-temperature amplifier without a transformer or a feedback line.
Citation
IEEE Transactions on Applied Superconductivity
Volume
11
Issue
1

Keywords

feedback circuts, SQUIDS, superconducting devices

Citation

Irwin, K. and Huber, M. (2001), SQUID Operational Amplifier, IEEE Transactions on Applied Superconductivity, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=6767 (Accessed February 23, 2024)
Created February 28, 2001, Updated October 12, 2021