Recent Advances in the Single-Flux-Quantum LSI Technology and Perspective on Superconductor Computers

Pascal Febvre

Masamitsu Tanaka, Akira Fujimaki, Koji Inoue

The recent trend and perspectives for high-performance microprocessors based on superconductor single-fluxquantum (SFQ) logic families are described. The rapid single-flux-quantum (RSFQ) and its energy-efficient derivatives are promising as a next-generation digital circuit technology for very-large-scale integration in the post-Moore's era because of the capability of ultrahigh-frequency operation over 100 GHz and low energy consumption. Several ongoing research projects as well as results reported, including several demonstrations of SFQ-based microprocessors and their components, are reviewed.

Andrea M. Herr

Akira Fujimaki

Advancement of superconductor digital electronics, especially Rapid Single Flux Quantum (RSFQ) logic circuit is described. Ultra short pulse of a voltage generated across a Josephson junction and release from charging/discharging process for signal transmission in RSFQ circuits enable us to reduce power consumption and gate delay. The power-delay products (PDPs) of RSFQ integrated circuits (ICs) are 4 or 5 orders of magnitude smaller than those of semiconductor ICs. The fabrication process technology and the related designing technology have been advanced, and RSFQ ICs have been applied to software-defined radio receivers, superconductor detector array systems, and supercomputers. Recently, several kinds of energy-efficient single flux quantum circuit have been proposed to obtain further advantage to semiconductor devices. The PDPs of these circuits become at least 1 order smaller than those of conventional RSFQ circuits.

Edward Leonard, Ted Thorbeck, Shaojiang Zhu +5 more

Akira Fujimaki, M. Tanaka, T. Kondo +8 more