Scientists have developed a new type of cryogenic computer chip capable of operating at such cold temperatures that it is approaching the theoretical limit of absolute zero.
This cryogenic system, called the Gooseberry, lays the groundwork for what could be a revolution in quantum computing – allowing a new generation of machines to perform calculations with thousands of qubits or more, while today’s most advanced devices include only dozens .
“The largest quantum computers in the world currently operate at only about 50 qubits,” explains quantum physicist David Reilly of the University of Sydney and the Microsoft Quantum Laboratory.
“This small scale is partly due to the limitations of the physical architecture that controls the qubits.”
That the physical architecture is constrained due to the extreme conditions that qubits need to perform quantum mechanical calculations.
Gooseberry chip (red) next to a qubit test chip (blue) and a resonator chip (purple). (Microsoft)
Unlike bits in traditional computers, which have either a value of 0 or 1, qubits occupy what is known as quantum overlap – an undefined and immeasurable state that can effectively represent both 0 and 1 in the same time, in the context of a mathematical operation.
This esoteric principle of quantum mechanics means that quantum computers can theoretically solve extremely complex mathematical problems that classical computers would never be able to answer (or take years to try).
As with conventional technology, however, more is always better, and so far researchers have been limited in the number of qubits they have been able to successfully implement in quantum systems.
One reason is that qubits need extreme levels of cold to operate (in addition to other controlled conditions), and the electrical wiring used in current quantum computing systems inevitably produces low but sufficient heat levels that disrupt thermal requirements. .
Scientists are looking for ways to solve this, but many quantum innovations to date have depended on the invention of bulky cabling to keep temperatures stable to increase the number of qubits, but that solution has its limits.
“Today’s cars create a beautiful range of wires to control signals; they look like a nest or a chandelier of inverted golden birds,” says Reilly.
“They’re nice, but basically impractical. It means we can’t scale cars to do useful calculations. There’s a real entry-exit block.”
The solution to this blockage could be Gooseberry: a cryogenic control chip that can operate at temperatures of “milikelvin” only a small fraction of a degree above absolute zero, as described in a new study.
This extreme thermal capacity means that it can stay inside the super-cold refrigeration environment with the qubits, interfacing with them and passing signals from the qubits to a secondary core that is outside in another extremely cold tank. , immersed in liquid helium.
By doing so, it eliminates the excess cables and the excess heat it generates, which means that contemporary qubit blockages in quantum computing could soon be a thing of the past.
“The chip is the most complex electronic system that works at this temperature,” Reilly told Digital Trends.
“This is the first time a mixed-signal chip with 100,000 transistors operates at 0.1 kelvin, [the equivalent to] –459.49 degrees Fahrenheit or –273.05 degrees Celsius. “
Finally, the team expects their system to allow thousands of qubits to be controlled by the cryogenic chip – about a 20-fold increase in what is possible today. In the future, the same type of approach could allow quantum computers to take another level.
“Why not think of billions of qubits?” Reilly told him Australian Financial Review. “The more qubits we can control, the better.”
Although it may be some time before we see this cryogenic discovery put into practice outside the laboratory, there is no doubt that we are looking at a big step forward in quantum computing, experts say.
“This will be transformative in the next few years,” Andrew White, director of the ARC Center of Excellence for Designed Quantum Systems, who was not involved in the study but oversees quantum research in Australia, told ABC News.
“It simply came to our notice then [developing quantum computers] do not use this chip, they will use something inspired by it. “
The findings are reported in Nature Electronics.