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arXiv · 2503.14712

Distribution and Purification of Entanglement States in Quantum Networks

Xiaojie Fan·Yukun Yang·Himanshu Gupta·C. R. Ramakrishnan
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Abstract

We consider problems of distributing high-fidelity entangled states across nodes of a quantum network. We consider a repeater-based network architecture with entanglement swapping (fusion) operations for generating long-distance entanglements, and purification operations that produce high-fidelity states from several lower-fidelity states. The contributions of this paper are two-fold: First, while there have been several works on fidelity-aware routing and incorporating purification into routing for generating EPs, this paper presents the first algorithms for optimal solutions to the high-fidelity EP distribution problem. We provide a dynamic programming algorithm for generating the optimal tree of operations to produce a high-fidelity EP, and an LP-based algorithm for generating an optimal collection of trees. Second, following the EP algorithms, this paper presents the first algorithms for the high-fidelity GHZ-state distribution problem and characterizes its optimality. We evaluate our techniques via simulations over NetSquid, a quantum network simulator.

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Xiaojie Fan, Yukun Yang, Himanshu Gupta, C. R. Ramakrishnan. 2025-03-24. Distribution and Purification of Entanglement States in Quantum Networks. https://arxiv.org/abs/2503.14712

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