Chinese scientists have created the world's first light-based quantum computer, called Jiuzhang, that can reliably demonstrate "quantum computational advantage", a milestone in which a quantum machine can solve a problem no classical supercomputer can tackle within a reasonable amount of time, according to a study published in the journal Science on December 4, 2020.
It is the second time that humanity has reached this milestone, after Google declared its 53-qubit quantum computer had achieved such a breakthrough last year.
However, Jiuzhang used a new method of manipulating 76 photons to do calculations instead of Google's, which uses superconductive materials.
Experts hailed the Chinese machine as a "state-of-the-art experiment" and a "major achievement" in quantum computing, as it proves the feasibility of photonic quantum computation, thus providing a fundamentally different approach to designing such powerful machines.
Quantum computers excel at running simulations that are impossible for conventional computers, leading to breakthroughs in materials science, artificial intelligence and medicine.
Moreover, most components of the light-based quantum machine can operate at room temperature, aside from its sensory equipment, which must be kept at -269.1 C.
This makes it significantly easier to make and maintain than superconducting quantum computers, the bulk of which must be kept at ultra-cold temperatures to ensure the materials can conduct electricity without any resistance.
Jiuzhang takes its name from an ancient Chinese mathematical text. It can perform an extremely esoteric calculation, called Gaussian boson sampling, in 200 seconds. The same task would take the world's fastest classical supercomputer, Fugaku, around 600 million years.