IBM connects its first modular cryogenic units, solving a critical infrastructure bottleneck on the path to launching the world’s first fault-tolerant quantum computer by 2029.
IBM has announced a major technical milestone in quantum infrastructure: the successful integration and cooling of two modular cryogenic cells operating within a unified ultra-cold system. The achievement addresses a fundamental scaling challenge in quantum computing by moving past isolated, legacy cylindrical cryostats to an expandable, multi-chip architectural framework. Capable of chilling processors to sub-15 millikelvin environments—a state colder than outer space—this modular refrigeration system establishes the physical foundation for interconnected, multi-chip quantum processors and brings IBM one step closer to deploying its fault-tolerant “IBM Quantum Starling” system by 2029.
The quest for commercially viable, fault-tolerant quantum computing has long extended beyond processor design alone. Superconducting quantum processors require specialized, ultra-cold environments to maintain delicate quantum states and prevent decoherence caused by thermal noise and environmental interference. Historically, quantum hardware has relied on individual cylindrical cryostats housing dilution refrigerators. While these isolated setups supported early breakthroughs—scaling systems from five-qubit prototypes to processors exceeding 1,000 qubits like IBM Quantum Condor—they inherently limit future expansion. Physical space constraints, internal wiring bottlenecks, and cross-chip interference create significant barriers to scaling a single processor further.
Recognizing that future performance hinges on distributing computational workloads across multiple interconnected chips, IBM has completely reimagined its cooling infrastructure. The company’s new modular cryogenic architecture departs from rigid cylinders in favor of expandable, box-shaped aluminum cells. Measuring over 2.4 meters high and 2.4 meters wide, each unit functions as an independent, fully equipped cryogenic environment featuring its own vacuum chamber, thermal shielding, and dilution cooling systems.
The structural design allows these modular units to sit side-by-side, creating tightly aligned configurations with minimal separation. Connected via specialized thermal shielding tunnels, the system allows quantum and classical wiring to pass between cells without disrupting the deep cryogenic environment. In recent tests at IBM’s facility in Poughkeepsie, New York, engineers successfully coupled two prototype modules. The joint system cooled down to 4 Kelvin—the temperature of liquid helium—in under five days, rapidly reaching an operational temperature below 15 millikelvin.
Crucially, the new architecture significantly expands internal capacity. Each module offers 2.75 cubic meters of vacuum chamber volume and roughly 0.53 square meters of available wiring space—up to twelve times the routing capacity of previous IBM quantum systems. This extra spatial volume accommodates the high-density cabling needed for advanced readout electronics and multi-chip interconnects.
Central to this multi-chip strategy is IBM’s “L-Coupler” technology. Designed to link separate quantum processing units (QPUs) across meter-scale distances within dilution refrigerators, L-Couplers enable direct, high-speed communication between adjacent chips. By leveraging these inter-chip connections, IBM aims to link multiple processors into a unified system containing at least 1,000 programmable qubits by 2027, with plans to integrate its IBM Quantum Nighthawk processors into the modular cells later this year for operational testing.
This modular approach directly accelerates IBM’s long-term quantum roadmap. By decoupling the refrigeration infrastructure from the underlying chip evolution, individual cells can host future processor iterations containing thousands of qubits without requiring a complete system redesign. Furthermore, key components from IBM Quantum System Two have been adapted into this architecture, allowing individual subsystems to be independently upgraded, tested, and refined.
As Jay Gambetta, Director of IBM Research, noted, scaling quantum computing for real-world industrial utility requires simultaneous breakthroughs across hardware, software, and systems engineering. By overcoming cryogenic spatial constraints and demonstrating multi-module cooling stability, IBM has resolved a crucial hardware bottleneck. This infrastructure milestone clears a clear path toward the 2029 target for IBM Quantum Starling—a system designed to deliver fully fault-tolerant quantum operations using advanced error-correction codes.
Dr. Jakob Jung is Editor-in-Chief of Security Storage and Channel Germany. He has been working in IT journalism for more than 20 years. His career includes Computer Reseller News, Heise Resale, Informationweek, Techtarget (storage and data center) and ChannelBiz. He also freelances for numerous IT publications, including Computerwoche, Channelpartner, IT-Business, Storage-Insider and ZDnet. His main topics are channel, storage, security, data center, ERP and CRM.
Contact via Mail: jakob.jung@security-storage-und-channel-germany.de