Unlike regular computers where data is stored in binary bits as 0 or 1, the “qubits” in quantum computers can exist as both at the same time. Stranger still, this information can be effectively “teleported” over any distance. Now, scientists from Austria and China have managed to create photons that exist as 0,1 and 2 simultaneously, and teleported these complex quantum states.
Quantum computers are poised to leave traditional computers and even supercomputers in the dust, and they owe their exponential increase in power to the fact that they go beyond binary. One “bit” of information isn’t limited to a 0 or a 1 – it can be either or both at the same time, much like Schrödinger’s infamous cat.
In theory, adding extra states boosts the power even more: throw in a 2, for example, and the range of possible states goes up exponentially. One qubit can be any individual value, or any pairing of two, or all three at once.
And now these theoretical higher-dimension quantum states have not only been demonstrated in lab experiments, but teleported as well. The team includes scientists from the Austrian Academy of Sciences, the University of Vienna, and the University of Science and Technology of China.
The team based its experiments on a long-standing favorite called the Bell test. In this, two photons are emitted in different directions at the same time, and when a certain property of one is manipulated and measured, the other usually ends up being the same. That information appears to be “teleported” to the second photon, no matter how far apart they are.
For the new study, the researchers adapted the classic experiment to teleport a three-level state, which they call a “qutrit.” The quantum state in this case is which of three optical fibers a photon is traveling through – remembering of course, that quantum physics allows a single photon to be in any or all three of the fibers at once.
The team used a multiport beam splitter to direct the photons, and then manipulated their states using auxiliary photons. By carefully controlling the interference patterns of these photons, the team was able to successfully teleport that quantum information to another photon, even though the two photons never interacted physically.
This experiment shows that quantum teleportation can not only be done in three dimensions, but theoretically it can be done in any number of dimensions.
This study is a step towards harnessing quantum mechanics for better electronics. In the not-too-distant future, a quantum internet could connect quantum computers together to send data incredibly fast through quantum teleportation.
The research was published in the journal Physical Review Letters.
Source: University of Vienna
