Optimal routing and end-to-end entanglement distribution in quantum networks

• Published in: Scientific reports Vol. 14; no. 1; pp. 19262 - 14
• Main Authors: Halder, Joy, Rajabov, Akhmadjon, Bassoli, Riccardo, Fitzek, Frank H. P., Fettweis, Gerhard P.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 20.08.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 639/166/987; 639/705/117; 639/705/258; Heuristic; Humanities and Social Sciences; Linear programming; multidisciplinary; Problem solving; Resource allocation; Science; Science (multidisciplinary)
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-024-70114-1

Quantum networks are designed to transmit quantum bits (qubits) among quantum devices to enable new network resources for the applications. Entanglement distribution and entanglement swapping are fundamental procedures that are required in several network operations. However, they are probabilistic operations, which can lead to severe network performance degradation. This article investigates the engineering problem of resource allocation in quantum networks, considering factors like entanglement distribution probability, quantum memory characteristics, and fidelity. We model this as an optimization model to obtain an optimal solution. In particular, we formulate an integer linear programming (ILP) and develop a heuristic algorithm, aiming to minimize the number of required entangled qubit pairs (Bell pairs or EPR pairs) in any adjacent pair in the quantum network. Extensive simulations are performed to compare the performance of proposed ILP and heuristic. In all the cases, the heuristic produces a comparable solution to the optimal one. Simulation results ensure that the value of maximum utilized Bell pairs in a quantum network highly depends on the value of the probability of entangled pairs established, considering the time in the quantum memory besides the number of incoming requests.