Dormant entanglement that can be activated or destroyed by the basis choice of measurements on an external system

Abstract

We propose a new form of entanglement called the dormant entanglement that can be activated or destroyed by the basis choice of measurements on an external system. The dormant entanglement without activation cannot be used as a quantum communication resource and has reduced correlation as compared to the Bell states. A particular form of the dormant entanglement is so weak that, without activation, no correlation in any basis can be observed between the entangled qubits. The dormant entanglement showcases a unique quantum behavior that the physical description of a local system remains incomplete until the information on all external systems entangled with the local system becomes available. For a potential application, we propose an n-party collective quantum communication channel that allows any 2 out of the n parties to activate an entanglement pair with the complete consensus of all other parties.