China’s Leading Quantum Research Group Declares Quantum Supremacy Achieved with Photonic Prototype

(Wired) Thursday, China’s leading quantum research group made its declaration of quantum supremacy, in the journal Science. A system called Jiuzhang produced results in minutes calculated to take more than 2 billion years of effort by the world’s third-most-powerful supercomputer.
“Quantum supremacy” is the moment a quantum machine does something impractical for a conventional computer.Last year, Google met the definition for quantum supremacy when its prototype quantum computer completed a calculation in minutes that its researchers estimated would have taken a supercomputer 10,000 years.
The two systems work differently. Google builds quantum circuits using supercold, superconducting metal, while the team at University of Science and Technology of China, in Hefei, recorded its result by manipulating photons, particles of light.
the indications that two fundamentally different forms of the technology can outperform supercomputers will buoy the hopes—and investments—of the embryonic industry.
One difference between Jiuzhang and Google’s Sycamore is that the photonic prototype is not easily reprogrammable to run different calculations. Its settings were effectively hard coded into its optical circuits. Christian Weedbrook, CEO and founder of Toronto quantum computing startup Xanadu, which is also working on photonic quantum computing, says the result is still notable as a reminder that there are multiple viable paths to making quantum number crunching work. “It’s a milestone in photonic quantum computing,” he says, “but also good for all of us.”
The Chinese team was led by Jian-Wei Pan, whose sizable research team has benefited from a Chinese government effort to be more prominent in quantum technology.