A superconducting tracking A/D converter

The design and fabrication of a superconducting A/D converter using Josephson technology are described. The 4-b A/D converter circuit was fabricated using a ten-level all-Nb technology. It uses a self-aligned lift-off process to define the Nb-Al/sub 2/O/sub 3/-Nb Josephson junctions. Results from experiments performed on the prototype system at a few kilohertz sampling rate are presented.<
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