DARPA asks industry to determine feasibility of cryogenic cables and connectors for quantum computing
ARLINGTON, Va. – U.S. military researchers are asking industry to determine the feasibility of developing high-density connectorized cryogenic cables for future use in superconducting classical computing, superconducting quantum computing and quantum annealing, and superconducting single-photon detector arrays.
Officials of the U.S. Defense Advanced Research Projects Agency (DARPA) in Arlington, Va., issued a solicitation on Monday for the High Density Connectorized Cryogenic Cables project.
Cryogenic cables are for use in low temperatures, and are made of low-thermal-conductivity metal materials on center and outer conductors, which minimize affect of low temperatures from outside the cables.
The goal is to create a new type of high-density data cable for superconducting electronics applications with high density, low attenuation, low crosstalk, and low heat load.
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One of the more difficult aspects about developing a superconducting electronics technology at low temperatures of about 10 millikelvin is the lack of suitable commercial input/output data cables, DARPA researchers explain.
Existing solutions often either are proprietary or are very-low- density coaxial cables. When they are available commercially, moreover, connectorized cryogenic cables often are only available from non-U.S. vendors.
High-quality cryogenic data cables are an extremely challenging. High quality cables should be simultaneously low loss and low heat load, which are goals that often are directly at odds.
DARPA researchers are looking for high-quality cables with many channels per cable, and with very low crosstalk. These competing requirements likely will demand a creative solution, experts say.
Ultimately, these cables should meet DARPA requirements, and seed a commercial technology that will enable a new generation of cryogenic information processing technologies.
Cables should have 8 to 16 channels per cable, with 128 to 256 channels per 4-inch vacuum feedthrough; -40 to -50 decibels of normalized crosstalk; 1.5 to 5 decibels per meter of insertion loss; and 2 to 5 nanowatts of heat load at 20 millikelvin.
Researchers are interested in how well cables can scale to higher connector densities, longer cable lengths, maximum operating frequencies; insertion loss at temperatures as high as room temperature; heat load at temperatures from 4 to 50 Kelvin; and signal phase matching within cables and cable-to-cable.
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In addition, researchers want to know the cable's minimum bend radius, customer-defined impedance values; compatibility with integrated passive components and cryogenic vacuum connections; mean time between failures at cryogenic temperatures; mean time between failures at mean thermal cycles; and expected commercial prices.
Phase-one contractors will perform a feasibility and design study, and produce a technical design for a high-quality cryogenic cable, and provide experimental or numerical evidence that their proposed solution will meet requirements.
DARPA may select performers from phase one for continuation into phase two to develop, manufacture, and characterize designs, and lay the groundwork for a new commercial cryogenic cabling solution.
In the program's first phase companies will compete for six-month worth as much as $175,000. Companies selected will be asked to submit phase-two proposals by invitation. The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR).
Companies interested should submit proposals no longer than 20 pages to the U.S. Department of Defense SBIR/STTR Proposal Submission website no later than 28 Sept. 2021 at https://www.sbir.gov/content/submission-proposals.
Email questions or concerns to DARPA at [email protected]. More information is online at https://sam.gov/opp/7fe6084a108c40ec872366829ef550cc/view.
John Keller | Editor-in-Chief
John Keller is the Editor-in-Chief, Military & Aerospace Electronics Magazine--provides extensive coverage and analysis of enabling electronics and optoelectronic technologies in military, space and commercial aviation applications. John has been a member of the Military & Aerospace Electronics staff since 1989 and chief editor since 1995.
