IBM has successfully connected two modular cryogenic systems and cooled them to below 15 millikelvin, marking another step toward its goal of building a fault-tolerant quantum computer by 2029.

The technology giant said Tuesday the new architecture is designed to eventually link hundreds of quantum chips inside a shared ultra-cold environment.

The two connected modules stand more than 8 feet tall and 8 feet wide. Initial tests showed they could cool to 4 Kelvin, roughly the temperature of liquid helium, in less than five days before reaching below 15 millikelvin, more than 180 times colder than deep space.

Keeping quantum processors at extremely low temperatures is crucial to maintaining the delicate quantum states needed for computation.

Each module also provides up to 12 times more wiring space than IBM’s widely used quantum systems, allowing more connections between quantum chips.

IBM plans to use its “L-coupler” technology to connect separate quantum processors so they can exchange information and operate as a larger system.

By 2027, the company aims to link multiple processors into a quantum computer with at least 1,000 programmable qubits. IBM Quantum Nighthawk processors are expected to be installed in the cryogenic modules later this year for further testing.

The technology is ultimately intended for IBM Quantum Starling, which the company plans to deliver in 2029 as what it expects to be the world’s first large-scale, fault-tolerant quantum computer.

“Bringing fault-tolerant quantum computers to industries depends on several fundamental advances,” IBM Research director and IBM Fellow Jay Gambetta said.

“The successful connection and operation of these cryogenic modules signals a leap forward in that direction,” he added.