Unconditional teleportation of continuous-variable entanglement

Summary form only given. Quantum teleportation enables reliable transportation of quantum information encoded in non-orthogonal quantum states. It is only possible with entanglement. Teleportation was originally proposed for discrete variables and later also for continuous variables. Discrete-variable teleportation has been performed experimentally for single-photon polarization states. Continuous variable teleportation has been realized for coherent states of electromagnetic field modes. But coherent states, although non-orthogonal, are very close to classical states. A real challenge for quantum teleportation is the teleportation of truly non-classical states like entangled states. This ´entanglement swapping´ was first introduced in the context of single-photon polarization states. It means to entangle two quantum systems that have never directly interacted with each other.