Chinese scientists have built the world's first quantum computing machine that goes beyond the early conventional or classical computers, paving way to the realisation of quantum computing.

Scientists announced their achievement at the Shanghai Institute for Advanced Studies of University of Science and Technology of China on Wednesday, Xinhua news agency reported.

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They believe quantum computing could in some ways dwarf the processing power of supercomputers. One analogy to explain the concept of quantum computing is that it is like being able to read all the books in a library at the same time, whereas conventional computing is like having to read them one after another.

Pan Jianwei, an academician of the Chinese Academy of Sciences and a leading quantum physicist, said quantum computing exploits the fundamental quantum superposition principle to enable ultra-fast parallel calculation and simulation capabilities.

In normal silicon computer chips, data is rendered in one of two states: 0 or 1. However, in quantum computers, data could exist in both states simultaneously, holding exponentially more information.

The computing power of a quantum computer grows exponentially with the number of quantum bits that can be manipulated. This could effectively solve large-scale computation problems that are beyond the ability of current classical computers, Pan said.

Due to the enormous potential of quantum computing, Europe and the US are actively collaborating in their research. High-tech companies, such as Google, Microsoft and IBM, also have massive interests in quantum computing research.

The research team is exploring three technical routes: systems based on single photons, ultra-cold atoms and superconducting circuits.

Pan explained that manipulation of multi-particle entanglement is the core of quantum computing technology and has been the focus of international competition in quantum computing research.

In the photonic system, his team has achieved the first 5, 6, 8 and 10 entangled photons in the world and is at the forefront of developments.

Pan said quantum computers could, in principle, solve certain problems faster than classical computers.

Despite substantial progress in the past two decades, building quantum machines that can actually outperform classical computers in some specific tasks — an important milestone termed "quantum supremacy" — remains challenging.

It is the first quantum computing machine based on single photons that goes beyond the early classical computer, and ultimately paves the way to a quantum computer that can beat classical computers. This achievement was published online in the latest issue of Nature Photonics this week.