Mini satellite paves the way for quantum communication worldwide
Mini satellite paves the way for quantum communication worldwide
researchers have set up a spacer record in quantum communication by sending a secret encryption key to South Africa almost 13,000 km from China. A cost -effective, slight 'microsatellite' was used.
The satellite was able to send light impulses with special quantum states from one roof in Beijing to another at Stellenbosch University near Cape Town. These impulses formed - one of the Chinese wall and one that shows part of the campus in Stellenbosch. This success, a type of encryption known as a quantum key distribution (QKD), is a step towards the possibility of sending ultra-safe messages between any, also very far away places. It was described on March 19 in the journal nature 1 .
The satellite called Jinan-1 is ten times lighter, 45 times cheaper and significantly more efficient than its predecessor, Micius, which was started in 2016 , reports Jian-Wei Pan, a quantum physicist at the University of Science and Technology in Hefei, China, who headed the project.
Pans team has also reduced the recipient of the floor station from 13,000 kg to portable 100 kg. "We would like to further develop the technology from proof of the principle to a really practical and useful application," he says. Pan adds that his team works with the telecommunications company China Telecom based in Beijing to start four other microsatellites for commercial applications in 2026.
"This is another milestone in the development of a global QKD network," says Alexander Ling, a quantum physicist at the National University of Singapore. The satellite represents "significant progress" in the real-time use of this type of encryption, adds Katanya Kuntz, a quantum physicist and co-founder of Qubo Consulting, a company in Calgary, Canada that helps other companies implement quantum technologies.
Uncrackable codes
Physicist believe that future quantum computers Many types of encryption can be cracked , but techniques like QKD offer "very strong certainty that a future quantum computer cannot read confidential communication," says Ling.
QKD is already used by banks and governments to transmit keys via fiber optic line. However, these cables absorb photons, which is limited to the distance from which the signal can be transmitted. Since light in the air is absorbed much more slowly than in a fiber optic cable, satellites could act as relays to transmit secret keys almost anywhere on earth.
quantum encryption is based on the idea that two parties share a secret key to encrypt a message so that only you can decrypt it.
pans experiment included the sending of light pulses, each in a 'super position', in which they also exist in two quantum conditions and either represent 1 or 0. By comparing the settings that the transmitter uses, with those that the recipient uses to measure the impulses, the two parties can develop a selection of measured 1 or 0en that are used as a safe key. If a listener tries to intercept the message, this disturbs the quantum conditions and generates noise, which indicates a compromise of the key.
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Li, Y. et al. Nature https://doi.org/10.1038/S41586-025-08739-Z (2025).