IEEE International Superconductive Electronics Conference (ISEC)

Operation of single-flux-quantum logic cells based on all-NbN integrated circuit technology

Hirotaka Terai, Kazumasa Makise, Zhen Wang

Published Jul 1, 2013• 3 citations

Abstract

We developed NbN-based SFQ circuits consisting of high-quality epitaxial NbN/AlN/NbN trilayer grown on MgO (100) substrate. The SFQ logic cells such as JTL, DC/SFQ converter, voltage driver, pulse splitter, TFF, and CB were designed by setting the critical current density JCat 2.5 kA/cm2. We succeeded in demonstrating correct operations of all the designed SFQ cells, but the JCrange allowing the operation was quite narrow as around 70% for the designed value. The circuit simulation revealed that the TFF cell requires the JCrange from 65% to 115% for the correct operation, while the DC/SFQ converter was not operational for the JCof more than 70%.

DOI: 10.1109/isec.2013.6604278

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