Input impedance of an amplifier based on a dc superconducting quantum interference device
- 1 October 1984
- journal article
- Published by AIP Publishing in Applied Physics Letters
- Vol. 45 (7) , 799-801
- https://doi.org/10.1063/1.95370
Abstract
The measured input impedance of an amplifier involving a coil tightly coupled to a dc superconducting quantum interference device (SQUID) is found to depend on the current and flux biases of the SQUID. Variations in the input inductance arise from the reflected dynamic inductance of the SQUID, and are in reasonable agreement with the predictions of an analog simulator. Variations in the input resistance, on the other hand, arise from feedback between the output of the SQUID and the input circuit, and are in approximate agreement with the predictions of a simple model.Keywords
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