Researchers prove safety of quantum cryptology

Scientists in Belgium and Spain have proved for the first time that new systems of quantum cryptology are much safer than current security systems. EU support for the research came from the Q-ESSENCE ('Quantum interfaces, sensors and communication based on entanglement') project, which received nearly EUR 5 million from 'Information and communication technologies' (ICT) Theme of the Seventh Framework Programme (FP7) and from the PERCENT ('Percolating entanglement and quantum information resources through quantum networks') project, which was awarded EUR 700 000 as part of a European Research Council (ERC) Starting Grant under FP7. The study was published in the journal Nature Communications.

By using keys that are generated using quantum particles, the transmission of data can be guaranteed by the very laws of physics, according to researchers at the Free University of Brussels (ULB) in Belgium and the Institute of Photonic Sciences in Barcelona in Spain. The laws of quantum mechanics state that observing a particle in its quantum state actually modifies that state, which means that in cases where quantum particles are used as keys in the transmission of data, 'spying' can be easily and immediately detected.

As the researchers noted in their paper, 'A central problem in cryptography is the distribution among distant users of secret keys that can be used, for example, for the secure encryption of messages'. They said that 'this task is impossible in classical cryptography unless assumptions are made on the computational power of the eavesdropper. Quantum key distribution (QKD), on the other hand, offers security against adversaries with unbounded computing power'.