On the Bipartite Entanglement Capacity of Quantum Networks

Abstract

We consider the problem of multi-path entanglement distribution to a pair of nodes in a quantum network consisting of devices with non-deterministic entanglement swapping capabilities. Multi-path entanglement distribution enables a network to establish end-to-end entangled links across any number of available paths with pre-established link-level entanglement. Probabilistic entanglement swapping, on the other hand, limits the amount of entanglement that is shared between the nodes; this is especially the case when, due to architectural and other practical constraints, swaps must be performed in temporal proximity to each other. Limiting our focus to the case where only bipartite entangled states are generated across the network, we cast the problem as an instance of generalized flow maximization between two quantum end nodes wishing to communicate. We propose a mixed-integer quadratically constrained program (MIQCP) to solve this flow problem for networks with arbitrary topology. We then compute the overall network capacity, defined as the maximum number of EPR states distributed to users per time unit, by solving the flow problem for all possible network states generated by probabilistic entangled link presence and absence, and subsequently by averaging over all network state capacities. The MIQCP can also be applied to networks with multiplexed links. While our approach for computing the overall network capacity has the undesirable property that the total number of states grows exponentially with link multiplexing capability, it nevertheless yields an exact solution that serves as an upper bound comparison basis for the throughput performance of easily-implementable yet non-optimal entanglement routing algorithms. We apply our capacity computation method to several networks, including a topology based on SURFnet -- a backbone network used for research purposes in the Netherlands.

References in corpus (24)

• Quantum cryptography: Public key distribution and coin tossing
• Long-distance quantum communication with atomic ensembles and linear optics
• Creation of entangled states of distant atoms by interference
• Deterministic delivery of remote entanglement on a quantum network
• Efficient long distance quantum communication
• Universal blind quantum computation
• End-to-end capacities of a quantum communication network
• Entanglement Percolation in Quantum Networks
• Path Selection for Quantum Repeater Networks
• Towards Large-Scale Quantum Networks
• Decentralized Base-Graph Routing for the Quantum Internet
• Shortcuts to quantum network routing
• Experimental demonstration of entanglement delivery using a quantum network stack
• Fundamental rate-loss tradeoff for the quantum internet
• Entanglement-Gradient Routing for Quantum Networks
• Entanglement generation in a quantum network at distance-independent rate
• Aggregating quantum repeaters for the quantum internet
• Designing Quantum Networks Using Preexisting Infrastructure
• Linear programs for entanglement and key distribution in the quantum internet
• Pre-Distribution of Entanglements in Quantum Networks
• End-to-End Capacities of Imperfect-Repeater Quantum Networks
• Entanglement Routing over Networks with Time Multiplexed Repeaters
• A Multiple-Entanglement Routing Framework for Quantum Networks
• An Architecture for Meeting Quality-of-Service Requirements in Multi-User Quantum Networks

Cited by in corpus (2)

• Spanning-tree-packing protocol for conference key propagation in quantum networks
• Simulation of entanglement based quantum networks for performance characterization