15 March 2011 ICFO in Nature Comm.

Black-box quantum cryptography

Researchers at the Free University of Brussels and the group led by Antonio Acin report on new results on quantum cryptography. The paper presents a security proof for device-independent quantum key distribution protocols. The security of these protocols is stronger than standard protocols because the proof is independent of the internal working of the devices. Indeed, the devices are just seen as black boxes producing an output given an input.

The authors provide a general security proof for a large class of quantum protocols in a model in which the key is generated by independent measurements. They show that device-independent quantum key distribution is, in principle, possible, being the obtained key rates comparable to those of standard quantum key distribution schemes.

The paper ‘Secure device-independent quantum key distribution with causally independent measurement devices’ has been published online in Nature Communications on March 15 by Dr. Lluis Masanes, Dr. Stefano Pironio and ICREA Prof. Antonio Acin.

- Dr. Stefano Pironio, former ICFOnian, has a FNRS position at LIQ, Brussels, Belgium.
- Dr. Lluis Masanes is a Research Fellow at ICFO.
- ICREA Prof. Antonio Acin leads the Quantum Information Theory group at ICFO.