Researchers from the National University of Singapore and NASA generated and detected quantum entanglement onboard a CubeSat nanosatellite orbiting the Earth.
The experiment demonstrated that a miniaturized source of quantum entanglement can operate successfully in space aboard a low-resource, cost-effective CubeSat that is smaller than a shoebox (10 cm × 10 cm × 10 cm).
The photon-pair source consisted of a blue laser diode that shines on nonlinear crystals to create pairs of photons. Achieving high-quality entanglement required a complete redesign of the mounts that align the nonlinear crystals with high precision and stability. The nanosatellite, named SpooQy-1, was deployed into orbit from the International Space Station on 17-June-2019. The instrument successfully generated entangled photon-pairs over temperatures from 16 °C to 21.5 °C.
“In the future, our system could be part of a global quantum network transmitting quantum signals to receivers on Earth or on other spacecraft,” said lead author Aitor Villar from the Centre for Quantum Technologies at the National University of Singapore. “These signals could be used to implement any type of quantum communications application, from quantum key distribution for extremely secure data transmission to quantum teleportation, where information is transferred by replicating the state of a quantum system from a distance.”
A report on the project was published in Optica, The Optical Society's (OSA) journal for high impact research.
The researchers are now working with RALSpace in the UK to design and build a quantum nanosatellite similar to SpooQy-1 with the capabilities needed to beam entangled photons from space to a ground receiver. This is slated for demonstration aboard a 2022 mission.
https://www.osa.org/en-us/about_osa/newsroom/news_releases/2020/quantum_entanglement_demonstrated_aboard_orbiting/
