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arXiv · 2508.00634

Swapped Entanglement in High-Dimensional Quantum Systems

S. M. Zangi·Chitra Shukla·Khalid Naseer·Saeed Haddadi
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Abstract

Entanglement swapping is a fundamental protocol in quantum information processing that enables the distribution of entanglement between distant quantum systems and plays a central role in quantum communication networks. In this work, we investigate entanglement swapping in arbitrary-dimensional quantum systems (qudits) and provide a quantitative analysis of the resulting entanglement distribution. Using I-concurrence and negativity as entanglement measures, we derive and analyze the average swapped entanglement generated by generalized Bell-state measurements. Our results show that increasing the system dimension enhances the efficiency of entanglement distribution, with high-dimensional systems exhibiting superior performance compared to their qubit counterparts. We further examine the implications of high-dimensional entanglement swapping for long-distance quantum communication and teleportation protocols relevant to quantum repeater architectures. In addition, we study the effects of noise by considering mixed entangled qudit states and analyze the behavior of the swapped entanglement as a function of fidelity and system dimension. The results demonstrate that higher-dimensional systems provide improved robustness against noise, highlighting their potential advantages for future quantum communication technologies.

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S. M. Zangi, Chitra Shukla, Khalid Naseer, Saeed Haddadi. 2026-08-13. Swapped Entanglement in High-Dimensional Quantum Systems. https://doi.org/10.1007/s11128-026-05289-9

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