Abstract
Quantum cryptography promises levels of security that are impossible to replicate in a classical world. Can this security be guaranteed even when the quantum devices on which the protocol relies are untrusted? This central question dates back to the early 1990s when the challenge of achieving device-independent quantum key distribution was first formulated. We answer this challenge by rigorously proving the device-independent security of a slight variant of Ekert’s original entanglement-based protocol against the most general (coherent) attacks. The resulting protocol is robust: While assuming only that the devices can be modeled by the laws of quantum mechanics and are spatially isolated from each other and from any adversary’s laboratory, it achieves a linear key rate and tolerates a constant noise rate in the devices. In particular, the devices may have quantum memory and share arbitrary quantum correlations with the eavesdropper. The proof of security is based on a new quantitative understanding of the monogamous nature of quantum correlations in the context of a multiparty protocol.
- Received 19 June 2014
DOI:https://doi.org/10.1103/PhysRevLett.113.140501
© 2014 American Physical Society
Erratum
Erratum: Fully Device-Independent Quantum Key Distribution [Phys. Rev. Lett. 113, 140501 (2014)]
Umesh Vazirani and Thomas Vidick
Phys. Rev. Lett. 116, 089901 (2016)
Viewpoint
Victory for the Quantum Code Maker?
Published 29 September 2014
To fend off potential hackers, researchers have taken a theoretical step closer to realizing a device-independent quantum cryptography protocol.
See more in Physics