Two hundred thousand samples. A top supercomputer would need about 700 seconds for each one, or roughly five years in total. China’s Jiuzhang quantum computer got through the lot in less than a second, according to its builders.
That works out to a speedup of 180 million times, a team led by Pan Jianwei claims. The South China Morning Post reported the result, and Interesting Engineering relayed it. Pan is widely known in China as the “father of quantum.”
A test on AI algorithms
Jiuzhang gained notice in 2020, when Pan’s group ran Gaussian boson sampling on it in 200 seconds. A conventional supercomputer would need an estimated 2.5 billion years for the same job. This time the researchers aimed at something closer to practical work. They put the machine through two algorithms common in artificial intelligence, random search and simulated annealing, which can strain even supercomputers.
The team chose its “noisy intermediate scale” hardware on purpose. Quantum computing is still in its infancy, and the work was meant to show that even early, error-prone machines can beat classical ones at useful tasks.
Jiuzhang computes with light. The researchers say that, unlike most quantum hardware, it does not need extremely low temperatures to run. Qubits in other designs, including the ones the US is developing, react to the slightest disturbance from their surroundings, which is why those machines sit in isolated, ultra-cold environments.
The team said the same computations could help in data mining, biological information, network analysis and chemical modeling. The findings were published last month in the peer-reviewed journal Physical Review Letters.
Jiuzhang 3.0
A newer version followed in October 2023. Jiuzhang 3.0 detected 255 photons in a boson sampling experiment, up from 113 in Jiuzhang 2.0. Pan’s team says it ran that task 10 quadrillion times faster than the fastest classical supercomputers. The machine is built for one specialized sampling problem rather than general computing, and the team itself says a general-purpose quantum computer is “still a long way” off.
Sources
- Jiuzhang 3.0: China’s Photonic Quantum Computer
- China's photonic quantum computer is 180 million times faster says 'father of quantum'
