Multipartite Entanglement Distribution using a Central Quantum-Network Node

We study the performance (rate and fidelity) of distributing multipartite entangled states in a quantum network through the use of a central node. Specifically, we consider the scenario where the multipartite entangled state is first prepared locally at a central node, and then transmitted to the end nodes of the network through quantum teleportation. As our first result, we present leading-order analytical expressions and lower bounds for both the rate and fidelity at which a specific class of multipartite entangled states, namely Greenberger-Horne-Zeilinger (GHZ) states, are distributed. Our analytical expressions for the fidelity accurately account for time-dependent noise encountered by individual quantum bits while stored in quantum memory. As our second result, we provide a comparison to an alternative scenario where the central node is unable to locally prepare GHZ states. Apart from these two results, we outline how the teleportation-based scheme could be physically implemented using ion traps or NV centers in diamond.