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arXiv · 2505.22484

Comparative analysis of robust entanglement generation in engineered XX spin chains

Eduardo K. Soares·Gentil D. de Moraes Neto·Fabiano M. Andrade
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Abstract

We present a numerical investigation comparing two entanglement generation protocols in finite XX spin chains with varying spin magnitudes ($s = 1/2, 1, 3/2 $). Protocol 1 (P1) relies on staggered couplings to steer correlations toward the ends of the chain. At the same time, Protocol 2 (P2) adopts a dual-port architecture that uses optimized boundary fields to mediate virtual excitations between terminal spins. Our results show that P2 consistently outperforms P1 in all spin values, generating higher-fidelity entanglement in shorter timescales when evaluated under the same system parameters. Furthermore, P2 exhibits superior robustness under realistic imperfections, including diagonal and off-diagonal disorder, as well as dephasing noise. These advantages stem from its ability to suppress the bulk population and minimize susceptibility to decoherence. Together, the scalability, efficiency, and noise resilience of the dual-port approach position it as a promising framework for entanglement distribution in solid-state quantum information platforms.

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Eduardo K. Soares, Gentil D. de Moraes Neto, Fabiano M. Andrade. 2025-07-20. Comparative analysis of robust entanglement generation in engineered XX spin chains. https://doi.org/10.3390/e27070764

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