Science

Toward the Realization of a Josephson Computer

S. Hasuo

Published Jan 17, 1992• 11 citations

Abstract

High-quality Josephson junctions, with both electrodes made from niobium and with an aluminum-oxide insulating barrier, were introduced in 1983. This niobium junction is very stable, reliable, controllable, and reproducible. Because of these excellent characteristics, these junctions can be applied to large-scale integrated (LSI) circuits, such as microprocessors having a few thousand gates and a few kilobits of memory. These circuits operate much faster and consume less power than any semiconductor circuit now available. Integrated Josephson circuits are now being tested in a closed-cycle refrigerator. The next step is to design a special-purpose, small-scale Josephson computer and to demonstrate its high performance.

DOI: 10.1126/science.255.5042.301

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