IEEE Transactions on Applied Superconductivity

Phase-Drop Realization Within RSFQ Digital Circuits With Reduced Josephson Current Density

Boyko Dimov, Thomas Ortlepp, Friedrich Uhlmann

Published Jun 1, 2007• 4 citations

Abstract

Within the classical Rapid Single-Flux Quantum (RSFQ) digital designs, the superconductive phase dropping necessary for the optimal SFQ data processing is realized with short sections of transmission lines serving as lumped inductances. This approach meets several hard restrictions about some promising future RSFQ applications requiring a drastic reduction of the junctions' critical currents. In this paper, we analyse these restrictions, and present an alternative and experimentally verified technique for superconductive phase dropping, which is compatible with any RSFQ fabrication technology. This technique provides compact and robust RSFQ digital circuits with highly improved fabrication yield.

DOI: 10.1109/tasc.2007.898556

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