Bound Entanglement: creation and activation.

The fact that entanglement cannot be generated using local operation and classical communication (LOCC) makes it a principal resource for accomplishing classically unachievable tasks and therefore it plays a key role in the field of quantum cryptography, communication and computation. However, producing entanglement is hard! in real experiment we often produce noisy entangled states that can be transformed by using distillation protocol to maximally entangled states. However, this distillation is not always possible, leading to a kind of trapped entanglement that we called bound entanglement. This is often mistakenly considered as useless.
In this talk I will present experimental realisation of bound entangled states, especially a tripartite bound entangled state that can be made to be distillable again. Remarkably our experiment is a first clear demonstration of super-additivity of distillable entanglement resources.