‘Star Trek’ Fiction Comes True, China Succeeds in Quantum Teleportation

Chinese scientists have achieved a breakthrough in much-awaited quantum teleportation when they successfully teleported photons to an orbiting satellite 300 miles above, paving the way for a future unhackable quantum Internet.

In Star trek, Scotty beams up crew to distant locations anytime and in the latest experiment, Chinese researchers were able to beam photons from a ground station in Ngari, Tibet to their Micius satellite, which is orbiting 300 miles above in the sky.

“Space-scale teleportation can be realised and is expected to play a key role in the future distributed quantum internet,” said the team of authors, led by Professor Chao-Yang Lu from the University of Science and Technology of China.

Explaining the process, their research paper said, “An arbitrary unknown quantum state cannot be precisely measured or perfectly replicated. However, quantum teleportation allows faithful transfer of unknown quantum states from one object to another over long distance, without physical travelling of the object itself.”

Teleportation also enhances capabilities of unhackable large-scale quantum networks and distributed quantum computation. In previous experiments, photons were lost in optical fibres or space channels after about 100-km distance.

Chinese experiment was based on satellite platform and space-based link, which can conveniently connect two remote points on the Earth with greatly reduced channel loss because most of the photons’ propagation path is in empty space, they said.

The team was able to teleport independent single-photon qubits from a ground observatory to a low Earth orbit satellite – through an up-link channel – with a distance of up to 1,400 km. To optimize the link efficiency and overcome the atmospheric turbulence in the up-link, a series of techniques are developed, including a compact ultra-bright source of multi-photon entanglement, narrow beam divergence, high-bandwidth and high-accuracy acquiring, pointing, and tracking (APT).

“We demonstrate successful quantum teleportation for six input states in mutually unbiased bases with an average fidelity of 0.80+/-0.01, well above the classical limit. This work establishes the first ground-to-satellite up-link for faithful and ultra-long-distance quantum teleportation, an essential step toward global-scale quantum internet,” they said.