Quantum Communication and Technologies

Figure 1 Entangled photon source for multi-photon quantum communication experiments used.

Quantum information technology is a fundamentally new way of harnessing Nature and truly revolutionary innovations are being invented, tested and commercialized on almost a daily basis. The success in quantum science and engineering has created several extremely valuable optical tools that operate exclusively under the rules of quantum mechanics and offer practical optical measurement and characterization techniques (quantum optical metrology) that have clear advantages over existing technologies. Quantum communication technologies are advancing swiftly to achieve their grand objective of being part of our daily lives. The past few years, in particular, have witnessed tremendous progress toward this end, and quantum key distribution networks have already been demonstrated in several ground breaking experiments.

We develop new quantum technologies, in particular those useful for photonic quantum communication. Our research focuses on applied experimental quantum information science, development of novel ultra-bright sources of entangled photons, scalable methods for transmission of quantum states over fiber and free-space channels. In the short term, we are building quantum links and, in the long term, large scale quantum networks. While the realisation of quantum communication schemes is routine work in the laboratory, non-trivial problems emerge in long-distance applications and in real world scenarios such as in fibers and free-space links and/or in high bit rate systems. We are also working towards integrating quantum and classical communication systems over commercial optical fibre as well as free-space communication infrastructure.

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