Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

AFIPS National Computer Conference (NCC)

Superconducting memories employing Josephson devices

W. Anacker

Published Jan 1, 1975• 2 citations
Publisher

Abstract

Experimental superconducting Josephson devices being investigated for use in digital logic and memory circuits have been demonstrated to switch in the 10 to 100 picosecond (1 picosecond = 10-12 sec) range. Projections based on the operation of individual logic circuits indicate that they may surpass semiconductor circuits in very high performance CPU's. This potential is based on the fact that these circuits dissipate extremely little energy, on the order of 10 to 1000 attojoules (attojoule = 10-18 joule), while operating with subnanosecond delays. It should, therefore, be possible to package Josephson devices very densely and interconnect them by properly terminated superconducting transmission lines so that the fast switching speed of individual circuits is retained throughout large logic networks.

DOI
10.1145/1499949.1500055

Related papers

Superconducting memories employing Josephson devices

W. Anacker

Experimental superconducting Josephson devices being investigated for use in digital logic and memory circuits have been demonstrated to switch in the 10 to 100 picosecond (1 picosecond = 10-12 sec) range. Projections based on the operation of individual logic circuits indicate that they may surpass semiconductor circuits in very high performance CPU's. This potential is based on the fact that these circuits dissipate extremely little energy, on the order of 10 to 1000 attojoules (attojoule = 10-18 joule), while operating with subnanosecond delays. It should, therefore, be possible to package Josephson devices very densely and interconnect them by properly terminated superconducting transmission lines so that the fast switching speed of individual circuits is retained throughout large logic networks.

afips•Dec 30, 1899•0 citations

Potential of superconductive josephson tunneling technology for ultrahigh performance memories and processors

W. Anacker

The potential of a new technology, based on the superconducting Josephson tunneling effect, has been assessed for use in high-speed computer systems. Josephson tunneling circuits for memory and logic functions can be switched at sub-nanosecond delay, do not require standby power, and dissipate extremely low energy, typically less than 10-13joule during fast switching operation. High-speed circuits with high packing densities, not limited by power dissipation problems, can therefore be expected. Low thermal noise at cryogenic temperatures ensures reliable operation despite the low energy switching signal. Practically lossless signal transmission via superconducting lines can be exploited for high-speed operation even when sizeable memory and logic modules are assembled. Two random access memory modules have been designed on the basis of single device experiments. Operational characteristics leading to the conclusion that 30 Mbit capacity, less than 1 watt refrigeration requirement (at 3.6° K) and cycle times of 40 ns (in one case) and 15 ns (in the second case), can be achieved are presented.

IEEE Transactions on Magnetics•Dec 1, 1969•72 citations

Josephson-junction logic and memory circuits

Gloria B. Lubkin

The superconducting tunnel effect predicted by Brian Josephson in 1962 is looking increasingly promising for another very practical application—as logic and memory circuits for computers. Josephson-junction circuits are capable of high switching speeds (50–100 picosec have already been obtained). And because such circuits operate at voltages comparable to the superconducting energy gap, the heat generated is typically microwatts, thousands of times lower than high-speed transistor circuits. The diminished heat-removal problem allows one to pack the Josephson circuits much closer than semiconductor circuits. Once high switching speeds are achieved, this packability becomes extremely important because then the major limitation on computer speed is how fast the electrical signal takes to move from one circuit to another.

Physics Today•Jun 1, 1978•0 citations

Superconducting digital electronics

Shuichi Tahara, Shinichi Yorozu, Y. Kameda +5 more

Superconducting devices have intrinsically superior characteristics to those of semiconductor devices. Presently, we can fabricate more than twenty thousand junctions on one chip using niobium technology. We have demonstrated the operation of a network system with a superconducting interconnection chip using voltage-state logic. Single flux quantum devices are promising for future superconducting applications because the clock frequency of SFQ logic is higher than that of voltage-state. We have proposed a high-end switch based on hybrid architecture using optical devices, semiconductors and SFQ devices. To demonstrate the high-speed operation of SFQ circuits, we developed an arbiter circuit that uses SFQ components and the arbiter circuit operates at 60 GHz. We also have developed a high Tc superconducting (HTS) SFQ sampler system for observing ultra-fast signal waveforms. In addition, we will discuss the prospects of future superconducting devices based on the fabrication technologies we developed.

IEEE Transactions on Applied Superconductivity•Mar 1, 2001•24 citations

Attojoule Superconducting Thermal Logic and Memories

Hui Wang, Niels Noordzij, M. Yu. Mikhaı̆lov +5 more

High Resolution Image Download MS PowerPoint Slide Due to stringent thermal budgets in cryogenic technologies such as superconducting quantum computers and sensors, electronic building blocks that simultaneously offer low energy consumption, fast switching, low error rates, a small footprint, and simple fabrication are pivotal for large-scale devices. Here, we demonstrate a superconducting switch with attojoule switching energy, high speed (pico-second rise/fall times), and high integration density (on the order of 10 –2 μm 2 per switch). It consists of a superconducting nanochannel and a metal heater separated by an insulating silica layer. We experimentally demonstrate digital gate operations utilizing these nanostructures, such as NOT, NAND, NOR, AND, and OR gates, with a few femtojoules of energy consumption and ultralow bit error rates <10 –8 . In addition, we build energy-efficient volatile memory elements with nanosecond operation speeds and a retention time over 10 5 s. These superconducting switches open new possibilities for increasing the size and complexity of modern cryogenic technologies.

arXiv:2407.07552•Nano Letters•Mar 10, 2025•5 citations

Superconducting/semiconducting hybrids and advance memory concepts for superconducting electronics. Final report, 1 May 1992-30 September 1997

M. R. Beasley, Horowitz

Superconducting logic circuits based on Josephson junctions (JJ) are the fastest, lowest power solid state digital circuit technology known. Large scale integration of such circuits has also been demonstrated. By contrast, current superconducting memory circuits based on flux quantization are not equivalently advanced. Very dense memory chips have not been possible to date and seem unlikely to come without new invention. The goal of this project was to explore alternative approaches to memory that would be compatible with Josephson junction logic circuits and capable of much denser memory arrays. Five new approaches were investigated ranging from modification to the current approach, use of semiconductor CMOS and wholly new concepts based on new physical principles. Three of these were identified as worth pursuing. They are use of cooled CMOS, use of cryogenic hybrid JJ/CMOS memory concepts and a totally new magnetoresistive approach to memory based on the superconductor/ferromagnet proximity effect.

•Nov 1, 1997•0 citations
Experimental superconducting Josephson devices being investigated for use in digital logic and memory circuits have been demonstrated to switch in the 10 to 100 picosecond (1 picosecond = 10-12 sec) range. Projections based on the operation of individual logic circuits indicate that they may surpass semiconductor circuits in very high performance CPU's. This potential is based on the fact that these circuits dissipate extremely little energy, on the order of 10 to 1000 attojoules (attojoule = 10-18 joule), while operating with subnanosecond delays. It should, therefore, be possible to package Josephson devices very densely and interconnect them by properly terminated superconducting transmission lines so that the fast switching speed of individual circuits is retained throughout large logic networks.
Experimental superconducting Josephson devices being investigated for use in digital logic and memory circuits have been demonstrated to switch in the 10 to 100 picosecond (1 picosecond = 10-12 sec) range. Projections based on the operation of individual logic circuits indicate that they may surpass semiconductor circuits in very high performance CPU's. This potential is based on the fact that these circuits dissipate extremely little energy, on the order of 10 to 1000 attojoules (attojoule = 10-18 joule), while operating with subnanosecond delays. It should, therefore, be possible to package Josephson devices very densely and interconnect them by properly terminated superconducting transmission lines so that the fast switching speed of individual circuits is retained throughout large logic networks.
The potential of a new technology, based on the superconducting Josephson tunneling effect, has been assessed for use in high-speed computer systems. Josephson tunneling circuits for memory and logic functions can be switched at sub-nanosecond delay, do not require standby power, and dissipate extremely low energy, typically less than 10-13joule during fast switching operation. High-speed circuits with high packing densities, not limited by power dissipation problems, can therefore be expected. Low thermal noise at cryogenic temperatures ensures reliable operation despite the low energy switching signal. Practically lossless signal transmission via superconducting lines can be exploited for high-speed operation even when sizeable memory and logic modules are assembled. Two random access memory modules have been designed on the basis of single device experiments. Operational characteristics leading to the conclusion that 30 Mbit capacity, less than 1 watt refrigeration requirement (at 3.6° K) and cycle times of 40 ns (in one case) and 15 ns (in the second case), can be achieved are presented.
The superconducting tunnel effect predicted by Brian Josephson in 1962 is looking increasingly promising for another very practical application—as logic and memory circuits for computers. Josephson-junction circuits are capable of high switching speeds (50–100 picosec have already been obtained). And because such circuits operate at voltages comparable to the superconducting energy gap, the heat generated is typically microwatts, thousands of times lower than high-speed transistor circuits. The diminished heat-removal problem allows one to pack the Josephson circuits much closer than semiconductor circuits. Once high switching speeds are achieved, this packability becomes extremely important because then the major limitation on computer speed is how fast the electrical signal takes to move from one circuit to another.
Superconducting devices have intrinsically superior characteristics to those of semiconductor devices. Presently, we can fabricate more than twenty thousand junctions on one chip using niobium technology. We have demonstrated the operation of a network system with a superconducting interconnection chip using voltage-state logic. Single flux quantum devices are promising for future superconducting applications because the clock frequency of SFQ logic is higher than that of voltage-state. We have proposed a high-end switch based on hybrid architecture using optical devices, semiconductors and SFQ devices. To demonstrate the high-speed operation of SFQ circuits, we developed an arbiter circuit that uses SFQ components and the arbiter circuit operates at 60 GHz. We also have developed a high Tc superconducting (HTS) SFQ sampler system for observing ultra-fast signal waveforms. In addition, we will discuss the prospects of future superconducting devices based on the fabrication technologies we developed.
High Resolution Image Download MS PowerPoint Slide Due to stringent thermal budgets in cryogenic technologies such as superconducting quantum computers and sensors, electronic building blocks that simultaneously offer low energy consumption, fast switching, low error rates, a small footprint, and simple fabrication are pivotal for large-scale devices. Here, we demonstrate a superconducting switch with attojoule switching energy, high speed (pico-second rise/fall times), and high integration density (on the order of 10 –2 μm 2 per switch). It consists of a superconducting nanochannel and a metal heater separated by an insulating silica layer. We experimentally demonstrate digital gate operations utilizing these nanostructures, such as NOT, NAND, NOR, AND, and OR gates, with a few femtojoules of energy consumption and ultralow bit error rates <10 –8 . In addition, we build energy-efficient volatile memory elements with nanosecond operation speeds and a retention time over 10 5 s. These superconducting switches open new possibilities for increasing the size and complexity of modern cryogenic technologies.
Superconducting logic circuits based on Josephson junctions (JJ) are the fastest, lowest power solid state digital circuit technology known. Large scale integration of such circuits has also been demonstrated. By contrast, current superconducting memory circuits based on flux quantization are not equivalently advanced. Very dense memory chips have not been possible to date and seem unlikely to come without new invention. The goal of this project was to explore alternative approaches to memory that would be compatible with Josephson junction logic circuits and capable of much denser memory arrays. Five new approaches were investigated ranging from modification to the current approach, use of semiconductor CMOS and wholly new concepts based on new physical principles. Three of these were identified as worth pursuing. They are use of cooled CMOS, use of cryogenic hybrid JJ/CMOS memory concepts and a totally new magnetoresistive approach to memory based on the superconductor/ferromagnet proximity effect.