Quantum repeaters and quantum key distribution: Analysis of secret-key rates

Limitations on Quantum Key Repeaters

A major application of quantum communication is the distribution of entangled particles for use in quantum key distribution. Owing to noise in the communication line, quantum key distribution is, in practice, limited to a distance of a few hundred kilometres, and can only be extended to longer distances by use of a quantum repeater, a device that performs entanglement distillation and quantum t...

Quantum Flows for Secret Key Distribution

In practice, the security of a Quantum Key Distribution (QKD) system relies not only on quantum mechanical principles, but it also significantly relies on the physical implementation of the protocol. Nowadays, technological detector loopholes of QKD systems have been demonstrated, and some successful attacks that exploit vulnerabilities of the Avalanche Photo Diodes (APD’s) have been performed....

Quantum cryptography and secret-key distillation

Quantum cryptography (or quantum key distribution) is a state-of-the-art technique that exploits the properties of quantum mechanics to guarantee the secure exchange of secret keys. This self-contained text introduces the principles and techniques of quantum cryptography, setting it in the wider context of cryptography and security, with specific focus on secret-key distillation. The book start...

Finite-key analysis for practical implementations of quantum key distribution

The lists of bits processed in quantum key distribution are necessarily of finite length. The need for finite-key unconditional security bounds was recognized long ago, but the theoretical tools have become available only very recently. We provide finite-key unconditional security bounds for two practical implementations of the Bennett–Brassard 1984 coding: prepareand-measure implementations wi...

Quantum Key Distribution