Nanobob: A Cubesat Mission Concept For Quantum Communication Experiments In An Uplink Configuration

We present a ground-to-space quantum key distribution (QKD) mission concept and the accompanying feasibility study for the development of the low earth orbit CubeSat payload. The quantum information is carried by single photons with the binary codes represented by polarization states of the photons. Distribution of entangled photons between the ground and the satellite can be used to certify the quantum nature of the link: a guarantee that no eavesdropping can take place. By placing the entangled photon source on the ground, the space segments contains only the less complex detection system, enabling its implementation in a compact enclosure, compatible with the 12U CubeSat standard (12 dm3). This reduces the overall cost of the project, making it an ideal choice as a pathfinder for future European quantum communication satellite missions. The space segment is also more versatile than one that contains the source since it is compatible with a multiple of QKD protocols (not restricted to entangled photon schemes) and can be used in quantum physics experiments, such as the investigation of entanglement decoherence. Other possible experiments include atmospheric transmission/turbulence characterization, dark area mapping, fine pointing and tracking, and accurate clock synchronization; all crucial for future global scale quantum communication efforts.
Comment: The CSUG Team: Yves Gilot, Etienne LeCoarer, Juana Rodrigo, Thierry Sequies, Vincent Borne, Guillaume Bourdarot, Alexis Christidis, Jesus Segura, Benoit Boulanger, Veronique Boutou, Mylene Bouzat, Mathieu Chabanol, Laurent Fesquet, Hassen Fourati, Michel Moulin, Jean-Michel Niot, Rodrigo Possamai Bastos, Bogdan Robu, Etienne Rolland, Sylvain Toru. Higher quality fig., more concise section 1.7