The Intelligence Advanced Research Projects Activity (IARPA) invests in high-risk, high-payoff research programs to tackle some of the most difficult challenges of the agencies and disciplines in the Intelligence Community (IC). IARPA is investing in breakthrough superconducting computing to enable energy efficient exaflop supercomputers. They could make an exaflop supercomputer that use 2 megawatts or less. The Cryogenic Computing Complexity (C3) is the name of the superconducting computer project.
Conventional computing systems, which are based on complementary metal-oxide-semiconductor (CMOS) switching devices and normal metal interconnects, appear to have no path to be able to increase energy efficiency fast enough to keep up with increasing demands for computation.
Superconducting computing could offer an attractive low-power alternative to CMOS with many potential advantages. Josephson junctions, the superconducting switching devices, switch quickly (~1 ps), dissipate little energy per switch (< 10^-19 J), and communicate information via small current pulses that propagate over superconducting transmission lines nearly without loss. While, in the past, significant technical obstacles prevented serious exploration of superconducting computing, recent innovations have created foundations for a major breakthrough. For example, the new single flux quantum (SFQ) logic circuits have no static power dissipation, and new energy efficient cryogenic memory ideas allow operation of memory and logic within the cold environment. Studies indicate that superconducting supercomputers may be capable of 1 PFLOP/s for about 25 kW and 100 PFLOP/s for about 200 kW, including the cryogenic cooler. Proof at smaller scales is an essential first step before any attempt to build a supercomputer. Early research suggests superconducting logic can switch at speeds north of 770GHz as shown by work at MIT
Success with the superconducting computing would also first enable Petaflop superworkstations or servers that only needed about 25 kilowatts of power.