Teleportation has become a standard operation in quantum optics labs around the world. The technique relies on the strange phenomenon of entanglement.
This occurs when two quantum objects, such as photons, form at the same instant and point in space and so share the same existence. In technical terms, they are described by the same wave function.
Theoretically, there are really only two ways this can(’t) be done – physical deconstruction at x and reconstitution at y, or the translation of one’s person into data to be transmitted, then reconverted into matter, like some organic fax machine.
The curious thing about entanglement is that this shared existence continues even when the photons are separated by vast distances. So a measurement on one immediately influences the state of the other, regardless of the distance between them.
Impossible? In 1993 an international group of six scientists, showed that perfect teleportation is possible in principle, or at least not against the laws of physics. More recently scientists both in the US and China have been trying. Just last year, Chinese scientists were able to “teleport” photons to a satellite 300 miles away, using a phenomenon called “quantum entanglement”.
Simply put this “spooky action at a distance” (as Einstein dubbed it) is where a pair of photons are able to simultaneously share the same state, even when separated by vast distances. Change the state of one particle, and weirdly, the other changes too, with no detectable connection.
In 1998, physicists at the California Institute of Technology (Caltech), along with two European groups, made IBM’s teleportation theory a reality by successfully teleporting a photon — a particle of energy that carries light.
The Caltech team read the atomic structure of a photon, sent this information across 3.28 feet (about 1 meter) of coaxial cable and created a replica of the photon on the other side. As predicted, the original photon no longer existed once the replica appeared.
In order to carry out the experiment, the Caltech group had to skirt a little something called the Heisenberg Uncertainty Principle.
As any boxed, quantum-state feline will tell you, this principle states that you cannot simultaneously know the location and the momentum of a particle. It’s also the main barrier for teleportation of objects larger than a photon.
But if you can’t know the position of a particle, then how can you engage in a bit of quantum teleportation?
In order to teleport a photon without violating the Heisenberg Principle, the Caltech physicists used a phenomenon known as entanglement. In entanglement, you need at least three photons to achieve quantum teleportation:
Since 1998, scientists haven’t quite worked their way up to teleporting baboons, as teleporting living matter is infinitely tricky. Still, their progress is quite impressive. In 2002, researchers at the Australian National University successfully teleported a laser beam, and in 2006, a team at Denmark’s Niels Bohr Institute teleported information stored in a laser beam into a cloud of atoms about 1.6 feet (half a meter) away.
“It is one step further because for the first time it involves teleportation between light and matter, two different objects,” explained team leader Dr. Eugene Polzik. “One is the carrier of information and the other one is the storage medium” [source: CBC].
In 2012, researchers at the University of Science and Technology of China made a new teleportation record. They teleported a photon 60.3 miles (97 kilometers), 50.3 miles (81 kilometers) farther than the previous record [source: Slezak]. Just two years later, European physicists were able to teleport quantum information through an ordinary optical fiber used for telecommunications [source: Emerging Technology from the arXiv].
In 2014, researchers Ronald Hanson and colleagues from the Technical University Delft in the Netherlands, demonstrated the teleportation of information between two entangled quantumbits three metres apart.
In 2016, Y. Wei proposed that particles themselves could teleport from one place to another. This is called particle teleportation. With this concept, superconductivity can be viewed as the teleportation of some electrons in the superconductor and superfluidity as the teleportation of some of the atoms in the cellular tube. Chinese physicists are trying to verify this concept experimentally.
Given these advancements, you can see how quantum teleportation will affect the world of quantum computing far before it helps your morning commute time. These experiments are important in developing networks that can distribute quantum information at transmission rates far faster than today’s most powerful computers.
It all comes down to moving information from point A to point B. But will humans ever make that quantum jaunt as well?