Since 1997 physicists around the world have been teleporting photons and the technique has become on time pretty standard and common. So common that is easy to do in every optic laboratory of the globe.
Teleport a photon means transfer that object from one location to another without travelling through the space. This is possible thanks to a phenomenon that physicists have named “quantum entanglement”. Quantum systems can become entangled through various types of interactions, and when this happen they remain in a “quantum superposition” and share a single quantum state until a measurement is made, so they share the same existance but are yet separated in space.
Unfortunately, entangled photons are fragile objects. They cannot travel further than a kilometre or so down optical fibres because the photons end up interacting with the glass breaking the entanglement.
However, physicists have had more success teleporting photons through the atmosphere. In 2010, a Chinese team announced that it had teleported single photons over a distance of 16 kilometres, a big lunge in the scientific horizon.
Now in 2012, that same team composed by Juan Yin of the University of Science and Technology of China in Shanghai and a bunch of mates say they have teleported entangled photons over a distance of 97 kilometres across a lake in China.
This has been possible for a series of adjustments to the optics and the laser gear in dotation
That’s an impressive feat for several reasons. The trick these guys have perfected is to find a way to use a 1.3 Watt laser and some fancy optics to beam the light and receive it.
The next pass, say the team, is to discover how evitate the air turbulence, the optic imperfections, but above all the beam widening. This factors cause a miss of the target of some photons, this could be translated in a lost of informations if the technology is used for that aim.
The team is oriented to create a new technology to allow the satellite-based quantum cryptography, say Juan: “The successful quantum teleportation over such channel losses in combination with our high-frequency and high-accuracy [aiming] technique show the feasibility of satellite-based ultra-long-distance quantum teleportation.”.
So the most important advance these guys have made is to develop a steering mechanism using a guide laser that keeps the beam precisely on target. As a result, they were able to teleport more than 1100 photons in 4 hours over a distance of 97 kilometres.