NANJING -- Chinese scientists have performed quantum experiments at various levels, including metropolitan, intercity, intercontinental, and in space.

They have now achieved a breakthrough with a drone, paving the way for a future where this "unhackable" encryption technology can be deployed in the real world.

The researchers from Nanjing University and University of Science and Technology of China have pioneered a global first by completing a quantum key distribution (QKD) experiment based on a drone platform.

It demonstrated that mobile platforms like drones are capable of carrying out more practical quantum tasks that require the capability to directly transmit single photons to end-users.

The QKD is based on a physical property in quantum mechanics that makes it impossible to create an independent and identical copy of an arbitrary unknown quantum state, thus, providing an "unhackable" way to exchange encrypted messages between remote users.

The team established a low-loss, high-fidelity optical quantum link between a small multi-rotor drone in flight and a ground station over a distance of 200 meters.

The experiments were done under nighttime conditions and during the day, with average error rates of approximately 2.28 percent and 3.86 percent, respectively, according to the study published last week in the journal Physical Review Letters.

The results confirmed the feasibility and reliability of using drone platforms to carry out practical photonic quantum tasks.

With the capability of secret key distribution using a drone, wireless communication can be expected with enhanced security in the quantum approach between mobile nodes toward a network, said the researchers.

They are also expecting to leverage high-altitude fixed-wing drones for wide-area QKD in the future, promising continuous, all-directional mobile quantum connectivity.