After saying nihao, or hello, to his Austrian counterpart some 7,000 kilometers away, Bai Chunli, president of the Chinese Academy of Sciences, completed the world's first intercontinental quantum communication in Beijing.
The dialogue between Bai and Anton Zeilinger, Austrian quantum physicist and President of the Austrian Academy of Sciences, on Sept. 29 could be ultra-secret if they keep it private between them.
Encrypted by quantum communication technology, what they said could not be wiretapped, intercepted or cracked.
Bai's greeting was first sent out through a control center in Beijing along the Beijing-Shanghai Trunk Line, the first of its kind for secure quantum telecommunication open for use the same day.
The 2,000-km trunk line had been connected through a ground station to the world's first quantum satellite Micius launched by China in August last year.
Micius was named after a fifth century B.C. Chinese philosopher and scientist who was credited as the first person to conduct optical experiments.
During their talk, Zeilinger expressed congratulations on the achievements Chinese scientists made in quantum communication and hoped to strengthen cooperation.
Earlier that day, Bai had video talks with staff in Hefei, Jinan, Shanghai and Urumqi ground stations through the trunk line.
Pan Jianwei, chief scientist of the trunk line, said the video call between Bai and Zeilinger involved a long distance and multiple nodes.
Given that some nodes were not built by Chinese scientists, the tests showed the ground-space quantum communication network was stable, compatible and good for practical use, said Pan.
Chinese businesses, including the Bank of Communications, the Industrial and Commercial Bank of China (ICBC) and Alibaba, have used the quantum communication technology for information transmission.
Zhu Yu, deputy head of the China Information Industry Association, expected the tests would attract more companies into the sector of quantum communication, and a brand new industrial chain would come into shape.
A number of encryption communication products including quantum USB key, a protecting device for mobile payment, have been put to the market.
In one or two years, China is likely to issue national standards for quantum key distribution equipment, according to sources close to the trunk line project.