IBM connects cryogenic modules in one environment, targeting 1,000 qubits by 2027

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IBM connects two box-shaped cryogenic modules into a single environment and cooled them below 15 millikelvin, linked by a thermally shielded tunnel carrying quantum cables between cells

The cooling technology is established dilution refrigeration; what is new is an enclosure that offers up to twelve times more wiring area and lets modules sit side by side with shorter interconnects in tow

IBM plans to install Nighthawk chips later this year, with a roadmap targeting 1,000 programmable qubits by 2027 and establishing fault tolerance in 2029

IBM has joined two cryogenic modules into a single environment at its Poughkeepsie facility and cooled the combined system to below 15 millikelvin, bringing it as close to absolute zero as possible.

The company said this was an important milestone on the road to IBM Quantum Starling, the fault-tolerant machine it intends to deliver in 2029.

IBM said the temperature is more than 180 times colder than deep space, and it is only part of the announcement, which furthers quantum computing considerably.

A story beyond temperature

Superconducting qubits need to sit a few thousandths of a degree above absolute zero, and a dilution refrigerator gets them there. To date, IBM has housed these inside tall cylindrical cryostats, one processor per can, an approach that dictates how every IBM Quantum System One in the field currently operates.

IBM has not replaced the refrigerator but rather modified the container: its new cryogenic cells are box-shaped, built from solid aluminum panels and framing, roughly three times the size of a kitchen fridge.

Their rectangular shape has an advantage: they can stand in a tight row rather than being spaced out as cylinders must be, and openings in the side walls let quantum cables run from one cell into the next. Multiple layers of thermal shielding wrap those cables to form what IBM calls a protected cryogenic tunnel, keeping the link between processors at operating temperature rather than forcing signals out through a warm gap and back down again.

IBM's achievement is demonstrating that it can run two previously independent cooling cells as one low-temperature environment, while offering 0.53 square meters of available wiring space and 2.75 cubic meters of vacuum chamber volume per cell.

IBM says this is up to twelve times more wiring room than its most widely used systems and addresses the constraint that has been quietly throttling superconducting quantum computers: every qubit you add needs control and readout lines running down into the cold, each line carries heat, and a cylinder runs out of cross-section long before one runs out of qubits.

Not only is IBM's new approach much more scalable than its previous ones, but it's goal here is different than what one would think at first glance given that It has already hit 1,000 qubits (its Condor processor already did so physically on a single chip in December 2023); its new approach is to have programmable qubits usable for computation across linked processors, a much different task than what IBM has already demonstrated.

Its 2027 target refers to qubits you can actually address and run a calculation on, spread across several chips linked together. That is a harder thing to deliver than a raw count, and IBM's roadmap, which also aims to have a fault-tolerant machine by 2029, is a reach by any measure, but one that is promising for a company that is at the forefront of quantum computing research and has just shown a bleeding-edge cooling enclosure to further its cause.