Comparative Analysis of Robust Entanglement Generation in Engineered XX Spin Chains

TL;DR

This paper compares two methods for generating entanglement in spin chains, finding that one method is more efficient and robust against noise.

Contribution

The dual-port protocol (P2) is shown to be more efficient and robust for entanglement generation in XX spin chains.

Findings

Protocol 2 (P2) generates higher-fidelity entanglement faster than Protocol 1 (P1) across all spin values.

P2 is more robust against disorder and dephasing noise compared to P1.

P2 remains effective under non-Markovian noise due to reduced excitation of bulk modes.

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. To further assess the resilience of both protocols in experimentally relevant settings, we employ the pseudomode formalism to characterize the impact of non-Markovian noise on the entanglement dynamics. Our analysis reveals that the dual-port mechanism (P2) remains effective even when memory effects are present, as it reduces the excitation of bulk modes that would otherwise enhance environment-induced backflow. 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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