Driven by the rapid progress in quantum hardware, recent years have witnessed a furious
race for quantum technologies in both academia and industry. Universal quantum …

Structured light, especially beams carrying orbital angular momentum (OAM), has gained
much interest due to its unique amplitude and phase structures. In terms of communication …

Quantum cryptography is arguably the fastest growing area in quantum information science.
Novel theoretical protocols are designed on a regular basis, security proofs are constantly …

In principle, quantum key distribution (QKD) offers information-theoretic security based on
the laws of physics. In practice, however, the imperfections of realistic devices might …

Secure communication is crucial in the Internet Age, and quantum mechanics stands poised
to revolutionize cryptography as we know it today. In this Review, we introduce the …

With the help of quantum key distribution (QKD), two distant peers are able to share
information-theoretical secure key bits. Increasing the key rate is ultimately significant for the …

Quantum key distribution (QKD) systems often rely on polarization of light for encoding, thus
limiting the amount of information that can be sent per photon and placing tight bounds on …

Quantum key distribution (QKD) together with one time pad encoding can provide
information-theoretical security for communication. Currently, though QKD has been widely …

We review the current status of single-photon-source and single-photon-detector
technologies operating at wavelengths from the ultraviolet to the infrared. We discuss …

The past decade has seen a dramatic increase in interest in new single-photon detector
technologies. A major cause of this trend has undoubtedly been the push towards optical …