Just 36 microseconds to solve an operation that would have taken at least 9,000 years: it is the new success achieved by quantum computers and was obtained by programming, for the first time, particles of light (photons).
Published in the journal Nature, it is the first result of its kind obtained with the programmable photonic processor Borealis of the Canadian startup Xanadu thanks to a particularly innovative technique that simplifies the development of these powerful tools.
"It is an interesting work and one that allows an important step forward in the deep understanding of the potential offered by quantum computing", commented Simone Severini, director of Quantum computing at Amazon Web Services (Aws).
The new machine created by the Xanadu researchers is one of the quantum computers that exploit photons within them in the role of qubits, that is the computing units of computers.
It is a rather simple machine compared to the one used two years ago by Google, which was the first to overtake traditional computers, and which is instead based on superconductors and to work it must be cooled to temperatures close to absolute zero (about less 270 degrees).
The success of Xanadu was to be able to beat a traditional super computer once again, performing a calculation in 36 microseconds that would have taken at least 9,000 years, but now using a programmable photonic processor and working at room temperature.
The one faced with the new chips is "a very difficult problem, known as Gaussian Boson Sampling, which takes a long time to solve by traditional computers that do not rely on quantum physics," added Severini.
"Solving it - he continued - allows us to identify groups of nodes within a complex network, for example to study neural networks or to understand the interaction between proteins".
At the heart of the success of the Borealis processor developed by Xanadu is a new method for coordinating the entry of photons into the processor.
In this case the light particles are produced by a single generator that creates a sort of train of aligned photons.
By inserting the single photons into special loops of shorter or longer length, it becomes possible to synchronize them, causing a delay on the first ones and reorganizing their entry into the chip, where the processing takes place.
Modifying the synchrony in a controlled form allows a sort of reprogramming of the possible moments of interaction between the various photons and in fact have a new type of chip, made in this case by chains of interconnected optical fibers and programmable according to the operation that you want to play.
"It is a really interesting result - commented Fabio Sciarrino, head of the Quantum Lab of the Physics Department of Sapienza in Rome - because quantum supremacy has been achieved by developing a platform that is both simple and innovative: the number is limited. of the necessary components and, in an ingenious way, the first programmable photonic processor in quantum supremacy regime is developed. All using photons with the same characteristics as those used in telecommunications,
