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IEEE Transactions on Applied Superconductivity

The distributed Josephson inductance phase shifter

D.J. Durand, J. Carpenter, E. Ladizinsky, L. Lee, Charles M. Jackson, Arnold H. Silver, A. D. Smith

Published Mar 1, 1992• 25 citations
Publisher

Abstract

The authors report on a novel microwave phase shifter featuring rapid electronic adjustment, continuous phase control true time delay operation, high device fault tolerance, and very broadband operation. By coupling a large number of superconducting quantum interference devices (SQUIDs) to a superconducting microstrip transmission line, a variable magnetic medium in which the wave velocity is controlled electronically is created. The authors have measured 60 degrees phase shift at 10 GHz, and wideband operation from 5 to 15 GHz for an 8-cm-long Nb transmission line coupled to 1600 SQUIDs, each containing a single Nb/AlO/sub x//Nb tunnel junction. The observed phase shift corresponds to a change in wave velocity of about 1 part in 60.>

DOI
10.1109/77.124932

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