量子卫星装置与全球量子网络

You can't sign up for the quantum internet just yet, but researchers have reported a major experimental milestone ¹ towards building a global quantum network - and it's happening in space. With a network that carries information in the quantum properties of single particles, you can create secure keys for secret messaging and potentially connect powerful quantum computers in the future. But scientists think you will need equipment in space to get global reach., ,Researchers from the National University of Singapore (NUS) and the University of Strathclyde, UK, have become the first to test in orbit technology for satellite-based quantum network nodes. , ,They have put a compact device carrying components ² used in quantum communication and computing ³ into orbit. And it works: the team report first data in a paper published 31 May 2016 in the journal Physical Review Applied ⁴., ,The team's device dubbed ⁵ SPEQS creates and measures pairs of light particles, called photons. Results from space show that SPEQS is making pairs of photons with correlated properties - an indicator ⁶ of performance., ,Team-leader Alexander Ling, an Assistant Professor at the Centre for Quantum Technologies (CQT) at NUS, said "This is the first time anyone has tested this kind of quantum technology in space.", ,The team had to be inventive to redesign a delicate, table-top quantum setup to be small and robust ⁷ enough to fly inside a nanosatellite only the size of a shoebox. The whole satellite weighs just 1.65-kilogramme.