Efficient Quantum Network Communication Using Optimized Entanglement-Swapping Trees

Quantum network communication is challenging, as the No-cloning theorem inquantum regime makes many classical techniques inapplicable. For long-distancecommunication, the only viable communication approach is teleportation ofquantum states, which requires a prior distribution of entangled pairs (EPs) ofqubits. Establishment of EPs across remote nodes can incur significant latencydue to the low probability of success of the underlying physical processes. The focus of our work is to develop efficient techniques that minimize EPgeneration latency. Prior works have focused on selecting entanglement paths;in contrast, we select entanglement swapping trees–a more accuraterepresentation of the entanglement generation structure. We develop a dynamicprogramming algorithm to select an optimal swapping-tree for a single pair ofnodes, under the given capacity and fidelity constraints. For the generalsetting, we develop an efficient iterative algorithm to compute a set ofswapping trees. We present simulation results which show that our solutionsoutperform the prior approaches by an order of magnitude and are viable forlong-distance entanglement generation.