China tests viability of quantum technology for secure communications
China has launched QUESS satellite that will test for the first time the viability of quantum technology for secure communications over long distances.
The 1.65kg Galassia nano-satellite, built by researchers at National University of Singapore (NUS), Singapore, carried a science payload of the size of a shoe box containing the basic components used in quantum communication and computing. Galassia was one of the six Singapore satellites that were launched by India’s Polar Satellite Launch Vehicle in December 2015.
The compact device, dubbed Small Photon-Entangling Quantum System (SPEQS), contains a laser diode, crystals, mirrors and photon detectors. It creates pairs of light particles called photons and measures the pairs’ properties—all on board the satellite.
According to the university website, analysis of data from the satellite “shows that SPEQS is making pairs of photons with correlated properties,” which is an indication that the device is performing as expected in orbit.