Chinese scientists have created a quantum link using drones

Chinese scientists managed to create a quantum communication link over the air — using drones. The aim is to repeat the same thing in space, but looks expensive.

The quantum line is usually based on transmission of single photons through fibre-optic channels. Researchers from China gave the protected data using drones, which are cheap to use. Two free-flying devices were on the destruction of 400 meters from each other. Each was removed at 200 meters from their ground stations. Thus a quantum communication channel was kilometer length.

Scheme of the experiment. Source.

One of the drones generate entangled pairs of infrared photons, one of them he passed to a ground station, the second — on another drone. The second they were caught and aired on their station. The results of the experiment showed that entangled was about 4% of the transmitted photons. It is a progress compared to the optical transmission lines where confusing are about 1% of photons.

Quantum entanglement means that the quantum States of two or more objects are interdependent. This method will allow to transmit quantum keys distributed over long distances. Thus it is possible to create an operational communication channels that are impossible to crack.