Entangled photons in the large

The technology of entangled photons now allows quantum entanglement experiments over large distances and in higher dimensional Hilbert spaces. Recently, long-distance quantum teleportation between the Canary Islands of La Palma and Tenerife was realized over a distance of 143 km. Such experiments open up the possibility of quantum communication with satellites. In higher-dimensional Hilbert spaces, states with orbital angular momentum (OAM) allow entanglement of very high quantum numbers and entanglements where each photon enjoys a more than 100 dimensional Hilbert space. Most recently, for Bell inequality experiments, the detection loophole was closed, which is an important step for secure quantumcommunication.