A visitor watches a screen introducing quantum computation at a conference in Hangzhou, capital of East China's Zhejiang Province in October 2015. Photo: VCG

When Google's scientists claimed that they had built world's first quantum computer with its calculation ability beyond today's most powerful supercomputers, a group of Chinese scientists developed a method in simulating quantum computing, and its test performance has reached world's leading levels.

The achievement was published on Monday on the international physics journal Physical Review Letters, entitled "General-Purpose Quantum Circuit Simulator with Projected Entangled-Pair States and the Quantum Supremacy Frontier," Wu Junjie, a leading expert QUANTA team from the National University of Defense Technology, told the Global Times on Tuesday.

The team proposed a method to realize an efficient simulator of quantum algorithms, and they applied the method to study random quantum circuits, which can quantify precisely the memory usage and the time requirements of random quantum circuits. The results can work as a theoretical benchmarking baseline for achieve quantum supremacy.

Wu said quantum computers' calculation ability has outperformed all supercomputers, and achieving quantum supremacy is a milestone in quantum computing development. 

Assessing this supremacy needs an efficient quantum computing simulator, which will also serve as a significant tool to accelerate scientific research on quantum computing, Liu Yong, a member of the QUANTA team, said.

The method was demonstrated on China's Tianhe-2 supercomputer, Wu said. 

Google last week claimed that it had achieved a "quantum supremacy" milestone, which means that its computer performed a designated mathematical calculation in 200 seconds that a conventional computer would need 10,000 years to complete.

Google's research on quantum supremacy also quoted Chinese achievement, Wu said.

China is also developing its own quantum computers. Scientists from Hefei-based University of Science and Technology of China have independently developed the country's first control system for future quantum computers in 2018. 

The country is also investing in a national laboratory for quantum information science in Hefei, East China's Anhui Province, due to open next year, which "costs $10 billion," according to media reports. 

The US has long dominated the field with support from tech giants like Google. But China "has closed the technological gap" with the US in quantum information science, according to a commission affiliated to the US Congress.