发表机构
University of Pisa; Fermi National Accelerator Laboratory; Northwestern University（比萨大学; 费米国家加速器实验室; 西北大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
针对光纤中光子损耗导致的长距离纠缠分发概率性问题，提出转导实现的超导量子中继器（TESQR），结合光子高速传输与超导高保真处理，实现确定性操作，平均分发率提升63%，纯化后20公里内保真度超0.8。
AI 中文摘要
长距离纠缠分发受到光纤中光子损耗和不可克隆定理的阻碍。光学量子中继器（QR）协议依赖于贝尔态测量（BSM），其本质上受限于概率性光子操作，且有50%的失败率。我们提出了一种构建量子中继器的混合方法，该方法结合了光子量子比特在光纤中的高传输速度与超导电路所实现的高保真量子处理能力。转导实现的超导量子中继器（TESQR）架构消除了对概率性BSM的需求，并允许确定性处理操作。TESQR框架始终在远程节点产生最终状态，而不是在光子损耗时中止，从而在特定参数范围内实现了确定性的纠缠分发。我们通过评估输出态保真度和使用现实噪声模型的纠缠分发成功概率来评估性能。此外，我们集成了一种纠缠纯化方案，并在QuTiP环境中通过数值模拟评估性能。我们的结果表明，对于纠缠交换，与纯光子架构相比，所提出的方案将纠缠分发率平均提高了63%，最高提高了159%。此外，经过纯化后，在长达20公里的距离上，端到端保真度超过0.8。
英文摘要
Long-distance entanglement distribution is hindered by photon loss in optical fibers and the nocloning theorem. Optical quantum repeater (QR) protocols rely on Bell state measurements (BSMs), they are intrinsically limited to probabilistic photon operations and fail 50% of the time. We propose a hybrid approach to building quantum repeaters that combines the high transmission speed of photonic qubits in optical fiber with the high-fidelity quantum processing capabilities enabled by superconducting circuits. The transduction-enabled superconducting QR (TESQR) architecture eliminates the need for probabilistic BSMs and allows deterministic processing operations. The TESQR framework always yields a final state at the remote nodes rather than aborting on photon loss, manifesting deterministic entanglement distribution within certain parameter regimes. We evaluate the performance by assessing output-state fidelities and success probabilities of entanglement distribution using realistic noise models. Additionally, we integrate an entanglement purification scheme and evaluate the performance through numerical simulations in QuTiP environment. Our results show that, for entanglement swapping, the proposed scheme improves the entanglement distribution rate by an average of 63% and by up to 159% compared with photonic-only architectures. Moreover, after purification, the end-to-end fidelities exceed 0.8 over distances up to 20 km.
