3QN: Towards A New UK Industry for Novel Quantum Receivers in Nascent Satellite QKD Global Markets

Quantum Key Distribution (QKD) is a well understood application of quantum technology and there are several metropolitan fibre networks already established for QKD services. However, key distribution is limited by absorption inside optical fibres which mean that transmissions over distances greater than about 150 km are impractical. Free space communications, though, does not suffer the same degree of attenuation and single photon communication with satellites orbiting the Earth at several hundred kilometres has been demonstrated. Satellites then, provide an ideal vehicle for distributing quantum key information across very large distances between end users spread across countries or continents. However, in order to benefit from the advances in satellite technology, a network of Optical Ground Receivers (OGRs) are required to receive and detect the photons carrying the key information. The UK, as a major player in the development of advanced optical & photonic technologies, is well positioned to address this future market for OGR. This project works with users to specify OGR requirements and prototypes and tests a QKD receiver, whilst designing and making plans for scaled manufacture in the UK.