Overview
- IBM, which joined and cooled two rectangular dilution‑refrigerator modules on Wednesday, August 19, 2026, brought the combined units to 4 kelvin in under five days and below 15 millikelvin shortly after.
- Each module’s vacuum enclosure offers up to 12 times more wiring space than earlier IBM systems, and engineers added a simulated 30‑microwatt heat load that held the modules at about 23 millikelvin during stressed testing.
- The linked boxes are empty of production processors for now, and IBM plans to install one Nighthawk processor per module later in 2026 to begin cross‑module operational testing.
- IBM says its L‑coupler superconducting links have produced best two‑qubit cross‑module fidelity of about 99.3 percent so far, with a company target near 99.9 percent for fault‑tolerant operations.
- The modular design aims to ease manufacturing, shipping and field servicing and to address wiring density and heat limits that block scale-up, but IBM still needs higher link fidelity and improved system reliability to reach planned multi‑module (~1,000 qubit) deployments in 2027 and the Starling fault‑tolerant system targeted for 2029.