Graphical Methods in Device-Independent Quantum Cryptography

Graphical Methods in Device-Independent Quantum Cryptography

We introduce a framework for graphical security proofs in device-independent quantum cryptography using the methods of categorical quantum mechanics. We are optimistic that this approach will make some of the highly complex proofs in quantum cryptography more accessible, facilitate the discovery of new proofs, and enable automated proof verification. As an example of our framework, we reprove a...

High-rate measurement-device-independent quantum cryptography

Device-independent security of quantum cryptography against collective attacks.

We present the optimal collective attack on a quantum key distribution protocol in the "device-independent" security scenario, where no assumptions are made about the way the quantum key distribution devices work or on what quantum system they operate. Our main result is a tight bound on the Holevo information between one of the authorized parties and the eavesdropper, as a function of the amou...

Device-independent quantum key distribution

Quantum key distribution allows two parties connected by a quantum channel to establish a secret key that is unknown to any unauthorized third party. The secrecy of this key is based on the laws of quantum physics. For security, however, it is crucial that the honest parties are able to control their physical devices accurately and completely. The goal of device-independent quantum key distribu...

Finite-size analysis of measurement-device-independent quantum cryptography with continuous variables