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06 Jun 2023

New Quantum Key Distribution Breakthrough Improves Communication Security

    Fully Passive Quantum Key Distribution

    Fully Passive Quantum Key Distribution

    Quantum key distribution (QKD) uses quantum mechanics to generate and distribute cryptographic keys that cannot be intercepted or cloned, making communication extremely secure. It has attracted worldwide interest because it promises information-theoretical security, which is the ultimate goal of communication security. However, the sources and detectors in the system can have side channels, which are vulnerabilities that can be exploited by hackers to compromise security. Although detector side channels have been addressed, source side channels have remained a challenge until recently. 

    A research team led by Professor Hoi Kwong LO and Dr Wenyuan WANG of HKU Department of Physics has proposed a QKD scheme without any modulators, which removes a major source of side channels on QKD sources. This breakthrough opens up new research directions to improve the security of practical QKD systems, making them even more secure in the future. Their findings has recently been published in Physical Review Letters.

    Journal title: 'Fully Passive Quantum Key Distribution', (Physical Review Letters, 2023). 

    Click here to view the journal paper.