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arXiv · 2502.09011

Statistical analysis of Multipath Entanglement Purification in Quantum Networks

Rajni Bala·Md Sohel Mondal·Siddhartha Santra
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Abstract

In quantum networks, a set of entangled states distributed over multiple, alternative, distinct paths between a pair of source-destination nodes can be purified to obtain a higher fidelity entangled state between the nodes. This multipath entanglement purification (MP-EP) strategy can exploit the network's complex structure to strengthen the entanglement connection between node pairs separated by appropriate graph distances. We investigate the network scenarios in which MP-EP outperforms entanglement distribution over single network paths utilising a statistical model of a quantum network and find that MP-EP can be an effective entanglement distribution strategy over a range of node separations determined by the average edge fidelities and probabilities of the network. We find that MP-EP can bost the entanglement connection between suitably separated node pairs to reach fidelities sufficient for a given quantum task thereby increasing the functionality of a quantum network. Further, we provide statistical criteria in terms of network parameters that can determine the regions of the network where MP-EP can be a useful entanglement distribution strategy.

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Rajni Bala, Md Sohel Mondal, Siddhartha Santra. 2025-02-13. Statistical analysis of Multipath Entanglement Purification in Quantum Networks. https://doi.org/10.1103/l9xq-zlcq

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