Traffic-Aware Initial Shared State for Proactive Entanglement Routing in Quantum Networks

Most quantum network schemes delay entanglement generation until a request arrives, causing slower processing. To this end, an approach of pre-establishing an initial shared state has emerged. However, the initial shared state must be versatile enough to accommodate all possible requests and may consume considerable qubits. It is crucial to minimize the number of qubits used while satisfying every possible request. We first introduce a 2 -approximation algorithm for the special case where each request consists of only one Bell or GHZ state requirement. Afterward, the 2 -approximation algorithm is extended to handle any possible request that may contain one or more requirements. Finally, via extensive simulation results, we show that our algorithm can outperform existing approaches by up to 29% in used qubits.