Superconducting Technology Assessment - nitrd

1.4.1 RSFQ READY FOR INVESTMENT
In the opinion of the panel, superconducting RSFQ circuit technology is ready for an aggressive, focused investment
to meet a 2010 schedule for initiating the development of a petaflops-class computer. This judgment is based on:
■ An evaluation of progress made in the last decade.
■ Projection of the benefits of an advanced very-large-scale integration (VLSI) process
for RSFQ in a manufacturing environment.
■ A reasonable roadmap for RSFQ circuit development that is coordinated with
manufacturing and packaging technologies.
1.4.2 RSFQ CAN LEVERAGE MICROPROCESSOR TECHNOLOGY
Although RSFQ circuits are still relatively immature, their similarity in function, design, and fabrication to semiconductor
circuits permits realistic extrapolations. Most of the tools for design, test, and fabrication are derived directly
from the semiconductor industry, although RSFQ technology will still need to modify them somewhat. Significant
progress has already been demonstrated on limited budgets by companies such as Northrop Grumman and HYPRES,
and in universities such as Stony Brook and the University of California, Berkeley.
Today, individual RSFQ circuits have been demonstrated to operate at speeds in the hundreds of GHz, and system
clocks greater than 50GHz seem quite attainable. The devices’ extremely low power will enable systems with greatly
increased computational capability and power requirements comparable to today’s high-end systems.
1.5 ROADMAP CREATED AND GOVERNMENT INVESTMENT NEEDED
Because there is no large commercial demand for superconductive electronics (SCE) technology either currently or
expected in the foreseeable future, private industry sees no financial gain in developing it. For this reason, government
funding is critical to SC technology’s development. Besides its use to NSA, SC will likely have applications for other
elements of the government, and once it has been developed, SC may eventually develop commercial applications
as well.
While the panel finds that the RSFQ technology is quite promising as a base for future HEC systems, significant developmental
effort will be needed to bring it to the state of maturity where it is ready for design and construction of
operational systems. The panel believes this technology is at a state of readiness appropriate for a major investment
to carry out this development.
To scope out the nature and magnitude of development effort needed, this report presents a detailed technology
roadmap, defining those RSFQ technology tools and components that must be developed for use in HEC in the
2010 time frame. The investment required is estimated between $372 and $437 million over five years.
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