标题： 被动量子互连：以更少的开销实现更高速率的高保真量子网络 显示英文标题

标题： Passive Quantum Interconnects: High-Fidelity Quantum Networking at Higher Rates with Less Overhead

摘要： 高保真、高速量子互连是可扩展量子技术的基本构建模块。腔辅助光子散射（CAPS）方法是一种有吸引力的替代方案，与基于光子发射和双光子干涉的常用主动协议不同：它提供了更高的成功概率和对缺陷更大的内在鲁棒性，同时保持被动操作，不需要复杂的原子激发序列或模块间同步。尽管有这些优势，由于现有协议和分析框架中估计的CAPS网络保真度和速率受到严重限制，CAPS并未成为量子互连协议的主要选择。在本工作中，我们通过协议改进消除了这些限制，通过对原子-腔动力学的深入分析，证明现有的或近期的光学腔质量足以实现0.999的保真度，满足高速网络所需的短光脉冲。我们表明，可以通过抑制串扰实现高效的时间复用操作，从而实现高速纠缠生成。我们还提出了一种混合网络配置，结合光子发射和CAPS门，无需外部光子源即可保持性能和鲁棒性。作为一个具体例子，当200个${}^{171}$Yb原子耦合到内部合作度为100的腔时，估计在0.999的保真度下，原子-原子纠缠生成速率为$4 \times 10^5~\mathrm{s}^{-1}$，通过使用多个波长信道，预计速度可以进一步提升到$10^6~\mathrm{s}^{-1}$以上。我们的结果确立了基于CAPS的网络协议作为扩展量子信息平台的首选候选方案。 显示英文摘要

摘要： High-fidelity, high-rate quantum interconnect is a fundamental building block of scalable quantum technologies. The cavity-assisted photon scattering (CAPS) approach is an attractive alternative to commonly used active protocols based on photon emission and two-photon interference: it offers higher success probability and greater intrinsic robustness to imperfections, while remaining a passive operation that does not require complex atom excitation sequences or intermodule synchronization. Despite these advantages, CAPS has not been a primary choice for quantum interconnect protocols since the estimated fidelity and the rate of CAPS-based networking have been severely limited in existing protocols and analysis frameworks. In this work, we eliminate these limitations by protocol improvements aided by a thorough analysis of the atom-cavity dynamics, to demonstrate that existing or near-term optical cavity qualities are sufficient for achieving a fidelity of 0.999 with short optical pulses required for high-rate networking. We show that efficient time-multiplexed operation is possible with suppressed crosstalk, enabling high-rate entanglement generation. We also propose a hybrid network configuration leveraging both photon emission and CAPS gates, eliminating the need for external photon sources while maintaining performance and robustness. As a concrete example, with 200 ${}^{171}$Yb atoms coupled to a cavity with internal cooperativity 100, atom-atom entanglement generation rate of $4 \times 10^5~\mathrm{s}^{-1}$ is estimated at a fidelity of 0.999, with further speedup beyond $10^6~\mathrm{s}^{-1}$ anticipated by the use of multiple wavelength channels. Our results establish the CAPS-based network protocol as a leading candidate for scaling quantum information platforms.