Global quantum networks for secure communication can be realized using large fleets of satellites distributing entangled photon pairs between ground-based nodes. Because the cost of a satellite depends on its size, the smallest satellites will be most cost-effective. This Letter describes a miniaturized, polarization entangled, photon-pair source operating on board a nano-satellite. The source violates Bell’s inequality with a Clauser–Horne–Shimony–Holt parameter of 2.60 ± 0.06 . This source can be combined with optical link technologies to enable future quantum communication nano-satellite missions.

Quantum random number generators find applications in both quantum and classical communications schemes, particularly in security protocols where they can be used as a source of random seed or key material. In this work, we describe the implementation of a quantum random number generator on-board a nanosatellite deployed in low Earth orbit. Our generator samples shot noise from an entangled photon-pair source based on spontaneous parametric down-conversion, linking the entropy of the output to the quantization of the down-converted beam. We present analyzed data from the orbiting instrument alongside data taken from a ground-based engineering model where the statistical test suites indicate a good match to the output from a uniform distribution. Finally, we use the source to implement a prototype for an off-grid randomness beacon. This work paves the way to future low Earth orbit based public quantum randomness beacons.

Quantum sources and receivers operating on-board satellites are an essential building block for global quantum networks. SpooQy-1 is a satellite developed at the Centre for Quantum Technologies, which has successfully demonstrated the operation of an entangled photon pair source on a resource-constrained CubeSat platform. This miniaturized and ruggedized photon pair source is being upgraded to be capable of space-to-ground quantum key distribution and long-range entanglement distribution. In this paper, we share results from SpooQy-1, discuss their relevance for the engineering challenges of a small satellite quantum node, and report on the development of the new light source.