The question of whether all entangled states can be used as a nonclassical resource has remained open so far. Here we provide a conclusive answer to this problem for the case of systems shared by two parties. We show that any entangled state $\sigma$ can enhance the teleportation power of some other state. This holds even if the state $\sigma$ is bound entangled.

• Received 6 October 2005

DOI:https://doi.org/10.1103/PhysRevLett.96.150501