Analysis of multipartite entanglement distribution using a central quantum-network node

Abstract

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 depolarizing noise encountered by individual quantum bits while stored in quantum memory, as verified using Monte Carlo simulations. As our second result, we compare the performance to the case where the central node is an entanglement switch and the GHZ state is created by the end nodes in a distributed fashion. Apart from these two results, we outline how the teleportation-based scheme could be physically implemented using trapped ions or nitrogen-vacancy centers in diamond.

Multiuser Entanglement Distribution in Quantum Networks Using Multipath Routing

“…We focus on the case N = |S| with each party receiving a single qubit of the multipartite state. Some multipartite SP routing protocols extended the concept of bipartite SP routing by pre-calculating paths between the users and a central device [14]- [16], [25] and then generating a Bell pair between the central device and each of the users. A multipartite state can then be generated from these Bell pairs using only local (qubit) operations and classical communication (LOCC).…”

An Architecture for Control of Entanglement Generation Switches in Quantum Networks

“…A quantum network hub that can store locally at least one qubit per linked node and distributes entanglement across these links has been studied [16], [17]. We refer to such a hub as an Entanglement Distribution Switch (EDS).…”

“…This system differs from our system because the central hub has qubits and/or quantum memories, whereas our system does not. In [16] the focus is on assessing the EDS performance in terms of the rate at which it creates n−partite entanglements, and in [17] the possible rate/fidelity combinations of GHZ states that may be supplied by an EDS [17] are studied. Maximum Weight scheduling is a type of solution to the problem of resource allocation which is based on assigning resources to sets of users with the largest service backlog.…”

Chirality-assisted enhancement of tripartite entanglement in waveguide QED

“…The need to establish and sustain entanglement among distant nodes of a quantum network for multiple users requires one to go beyond the bipartite entanglement and enter the domain of multiparty entanglement 24 , 25 . The multipartite entanglement offers new types of applications in quantum computation, for instance, in the context of cluster states and measurement-based computing 26 – 28 .…”