IBM on Wednesday announced that it has successfully joined and cooled two cryogenic quantum "fridges," demonstrating a modular architecture designed to eventually link hundreds of quantum chips into more powerful quantum computers.
Big Blue cast the development as a milestone on the company's path to delivering IBM Quantum Starling in 2029 , which IBM expects will be the world's first fault-tolerant quantum computer and will integrate advances across error correction, processor design, decoding and systems engineering.
"Bringing fault-tolerant quantum computers to industries depends on several fundamental advances," Jay Gambetta, director of IBM research and IBM fellow, said in a statement.
"The successful connection and operation of these cryogenic modules signals a leap forward in that direction," he continued, "and will accelerate our progress alongside continued innovation in quantum hardware, software, and algorithms."
IBM explained that the quantum fridges, which are more than eight feet tall and eight feet wide, can be jointly cooled down to 4 Kelvin (the temperature of liquid helium) in under five days and reach a final temperature below 15 millikelvin shortly thereafter.
"Temperature is a challenge because materials that are superconducting are only stable at extremely low temperatures," explained Luke Wang, an equity analyst with Morningstar Research Services in Chicago.
"Qubits are also fragile, and temperature is one of the factors that can impact their performance," he told TechNewsWorld.
IBM also noted that each module’s vacuum enclosure offers up to 12 times more wiring space than the most widely used IBM quantum systems, enabling more chip-to-chip connections both within and between modules.
The company plans to install Nighthawk processors in the modules later this year for additional testing and aims to use the architecture to support at least 1,000 programmable qubits by 2027.
"Superconducting qubits have to sit at a few thousandths of a degree above absolute zero, colder than deep space, inside a dilution refrigerator," explained Yuval Boger, chief commercial officer for QuEra Computing , a builder of quantum computers using neutral atoms, in Boston.
"That works well for tens or hundreds of qubits, but every qubit you add brings more control wiring into the cold environment, and each wire carries heat," he told TechNewsWorld. "So cooling power, wiring density, and footprint all become constraints as you scale, which is a major reason modular, chip linking approaches like this one are being pursued."
Boger agreed that the development is a meaningful engineering milestone.
"For years the hard question in superconducting quantum computing has been how to grow beyond a single chip," he said. "Linking many chips into one machine reframes scaling as a modular systems problem, which is how classical supercomputing matured."
However, he added: "It is worth being precise about what is being scaled. This is progress on physical qubits and interconnects. If successful, it will reduce the significant cost, energy consumption, and space that superconducting qubits require by reducing the number of cryogenic cooling units."
Sam Lucero , an independent strategy and research consultant in Phoenix and former quantum computing analyst with global research and consulting firm Omdia , termed the IBM development incremental. "I think it's an incremental step toward their path to creating infrastructure that scales better th…