Twin atoms: A source for entangled particles

Quantum experiments that could previously only be performed with photons are now also possible with atoms: Beams of entangled atoms have been produced at TU Wien (Vienna). Heads or tails? If we toss two coins into the air, the result of one coin toss has nothing to do with the result of the other. Coins are independent objects. In the world of quantum physics, things are different: quantum particles can be entangled, in which case they can no longer be regarded as independent individual objects, they can only be described as one joint system. For years, it has been possible to produce entangled photons - pairs of light particles that move in completely different directions but still belong together. Spectacular results have been achieved, for example in the field of quantum teleportation or quantum cryptography. Now, a new method has been developed at TU Wien (Vienna) to produce entangled atom pairs - and not just atoms which are emitted in all directions, but well-defined beams.