The science of quantum information has arisen over the last two decades centered on the
manipulation of individual quanta of information, known as quantum bits or qubits. Quantum …

Quantum information is a rapidly advancing area of interdisciplinary research. It may lead to
real-world applications for communication and computation unavailable without the …

We propose several methods for quantum key distribution (QKD) based on the generation
and transmission of random distributions of coherent or squeezed states, and we show that …

Electrically driven semiconductor lasers are used in technologies ranging from
telecommunications and information storage to medical diagnostics and therapeutics. The …

Quantum continuous variables are being explored,,,,,,,,,,,, as an alternative means to
implement quantum key distribution, which is usually based on single photon counting. The …

Continuous-variable systems realized in quantum optics play a major role in quantum
information processing, and it is also one of the promising candidates for a scalable …

These notes originated out of a set of lectures in Quantum Optics and Quantum Information
given by one of us (MGAP) at the University of Napoli and the University of Milano. A quite …

The impossibility of perfectly copying (or cloning) an unknown quantum state is one of the
basic rules governing the physics of quantum systems. The processes that perform the …

We show that no distillation protocol for Gaussian quantum states exists that relies on (i)
arbitrary local unitary operations that preserve the Gaussian character of the state and (ii) …

A continuous key-distribution scheme is proposed that relies on a pair of conjugate quantum
variables. It allows two remote parties to share a secret Gaussian key by encoding it into one …