Laser terminal for CubeSat-based QKD-Satellite

Kurzfassung

With the increasing computational capability of classical- and quantum computers, there is also the demand of enhancing the security of encryption. Quantum Key Distribution (QKD) is one technology which plays an important role in future quantum secure networks with its unique property of detecting an eavesdropper during key exchange. The existing fiber optic infrastructure can already be used for QKD, but due to the signal attenuation, it is limited to a distance of a few 100km. To overcome this limitation, a free space optical satellite link can be implemented. DLR's institute of communications and navigation (DLR IKN) develops laser terminals as well as systems for optical ground stations (OGS) to perform QKD. This also includes equipment for simulation and on-ground tests to verify optical link performance in presence of atmospheric turbulences. DLR IKN contributes to the development of a satellite-based QKD system as a member of the QUARTZ consortium which is part of the ESA ScyLight programme. In the initiative "Quantum Network" (QuNET), initialized from the Federal Ministry of Education and Research, DLR IKN develops free space optical laser terminals for a QKD link from ground to ground, air to ground and satellite to ground. Recently, DLR IKN finalized a CubeSat-based laser terminal to be used for QKD experiments in the scope of the project QUBE and will further develop a successor for performing complete quantum key exchange from a CubeSat to ground in the project QUBE II.