The range of direct links such as those used for MDI-QKD is up to a few hundred kilometers [RV15, YLT14], which limits its use to metropolitan areas. For QKD to reach farther one must employ either quantum repeaters or satellite channels for which the loss is non-exponential with distance [RB17]. The promise of satellite QKD has been realized several places around the globe with major breakthroughs demonstrated in China [JY17, SKL18]. In Canada a quantum satellite project (QEYSSat) [TJ14] has been fully funded and is set for launch in 2024.
Current projects
In the QCloudLab we have constructed a quantum satellite ground station with the ability to establish communication links with satellite, and are developing capability to connect satellite links to optical fibre links and quantum memory. Such a quantum satellite ground station, connected to an urban quantum network, will enable Calgary and Alberta to be a major part of the worldwide quantum communication infrastructure.
