Two groups have demonstrated quantum teleportation — the remote exchange of quantum states — across cities using ordinary fibre-optic links.

In quantum teleportation, pairs of particles — typically photons — are created that share a common quantum state. Each particle is sent to a different location, and manipulating one affects the measurable properties of the other, so enabling the transfer of information. The teams, one led by Jian-Wei Pan at the University of Science and Technology of China in Shanghai and the other by Wolfgang Tittel at the University of Calgary in Canada, demonstrated data transfer between devices that were several kilometres apart in Hefei, China, and Calgary, respectively. Although such a feat had been achieved before with visible-light photons, the current work used infrared photons, which are compatible with existing communications networks.

Teleportation could enable future quantum computers to exchange data.

Nature Photon. http://dx.doi.org/10.1038/nphoton.2016.179; http://dx.doi.org/10.1038/nphoton.2016.180 (2016)