Next-Generation Satellite Telecommunications Entangled Photon Source (NextSTEPS)

Quantum Computers have the potential to offer a huge range of benefits. By increasing processing power exponentially, they will unlock new, exciting capabilities and improve our current capacity considerably. This does however put at risk technologies which have long relied on computational expense for their function. An example of this is encryption, which keeps data secure via the use of asymmetrical mathematical problems which are beyond the capability of most classical computers. These problems will, however, be easily solvable by quantum computers, creating a problem referred to as the "Quantum Apocalypse".

There are currently two front-runner technologies to keep data secure in a post-quantum world. Post-Quantum Cryptography (PQC) aims to provide mathematical challenges which a quantum computer will not be able to solve, as a new iteration of current methodologies. Quantum Key Distribution (QKD) offers a novel method for distributing keys which enables robust symmetrical encryption techniques, with the key transfer mechanism being protected by fundamental laws of physics, as opposed to mathematical complexity. Both are receiving significant focus and investment, with the most likely outcome being hybrid solutions incorporating the benefit of each.

To support the roll out of these new technologies, space has emerged as a critical component in networks for quantum security. Satellites offer the ability to distribute information globally, and also allow for free-space optical transfer, which isn't limited by distance in the same way as terrestrial fibre networks. The Chinese Micius satellite demonstrated a number of fundamental technologies in 2016, which has led to a race to match this achievement in other countries. As such a number of satellite missions orientated towards quantum security are in development, predominantly focusing on cost effective small- or nanosatellites.

Within this landscape a consortium featuring Craft Prospect, Alter Technologies and Fraunhofer Centre for Applied Photonics has formed to develop the next generation of products for space-based quantum security. NextSTEPS will look to build a benchtop demonstrator of an entangled photon source. The benefits of this type of unit are increased security and future relevance, due to the need for the creation of networks of quantum computers. The work will also consider the requirements of the unit for use in space, and in particular for low Size, Weight and Power (SWaP) satellite platforms such as nanosatellites. Through the project the team will create enabling technologies for future quantum computing networks while also defining near-term entangled-source QKD products.