Cryptography

Keeping quantum secrets

Journal name:
Nature
Volume:
503,
Pages:
168–169
Date published:
DOI:
doi:10.1038/503168e
Published online

Quantum cryptographers have used devices in Switzerland and Singapore to deliver a secret message in the form of a committed bit — the value of which is kept hidden until a designated time.

Bit commitment is potentially useful for voting and other applications in which privacy is key, but ultra-secure quantum commitment schemes have proved difficult to implement.

Felix Bussières of the University of Geneva in Switzerland and his colleagues experimentally demonstrated a protocol proposed in 2012 for keeping committed bits secret. The technique, which relies on the constancy of the speed of light, can prevent insecure communication between remote locations for periods of up to 15 milliseconds, perhaps long enough to enable high-speed stock trading.

Phys. Rev. Lett. 111, 180504 (2013)

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