Quantum teleportation is the mystical, far-off in the future idea where quantum information encoded into particles of light can be transferred from one place to another remotely. Except it's not far-off in the future — it just happened. Teleportation is real and it is here.
The teleportation occurred over several kilometres of optical fibre networks in the cities of Hefei in China and Calgary in Canada.
The two independent studies show that quantum teleportation across metropolitan networks is technologically feasible, and pave the way towards future city-scale quantum technologies and communications networks, such as a quantum internet.
Quantum teleportation over fibre optic networks has the potential to greatly improve the security and strength of internet connections. However, long-distance quantum teleportation using a fibre network requires independent light sources, and this presents a technological challenge: the light beam from one source needs to remain indistinguishable to the light beam from the other source after travelling through several kilometres of fibre that is laid through a changing environment.
To overcome this, the research groups independently developed several feedback and synchronisation mechanisms to enable their teleportation experiments.
Qiang Zhang, Jian-Wei Pan and colleagues implemented their field test in Hefei, China and used light at a telecommunication wavelength (as used in current telecommunications networks) to minimise the rate at which the signal light loses intensity in the fibre.
Wolfgang Tittel and colleagues conducted their test in Calgary, Canada, but used photons at both a telecommunication wavelength and a wavelength of 795 nm, which allowed their quantum teleportation experiment to run faster than Zhang, Pan and colleagues' experiment, but at a reduced fidelity.
So together, we have photons both retaining light, and travelling fast. This is super exciting. These studies will now form the basis of further experiments, and bring us even closer to that elusive dream of teleportation of matter. Well, that's my dream, anyway. Even if we aren't made of quantum information encoded into particles of light. Yeah, that might be a stumbling block.
Would you try teleportation for yourself? Let us know in the comments!