AI 中文总结
本研究采用与多原子量子存储平台兼容的集成窄带光子源，实现了高可见度的纠缠交换，完成了覆盖1.6 THz的系统级稳定，为现场部署量子中继器解决了关键技术挑战。
AI 中文摘要
第一代量子中继器的可行实现方案预计需要基于原子的量子存储系统与光子源接口。集成光子学为量子中继器的光纤化、现场部署操作提供了有前景的解决方案，但许多领先的量子存储平台需要窄带光子，而这类光子难以通过集成光子学生成。窄带光子在实现纠缠交换时也带来了重大技术挑战，尤其在系统级稳定方面。本研究通过采用带宽与多个基于原子的量子存储平台兼容的最先进集成光子源，演示了纠缠交换，从而应对了这些基础和技术挑战。我们获得了背景扣除后的净HOM可见度为0.99±0.01，表明光子具有高不可区分性和纯度；净交换态可见度为𝒱=0.88±0.06，证明最终纠缠足以违反贝尔不等式。实验中，每对光子源使用独立的泵浦激光器，其频率差异很大，以模拟不同中继器节点或平台之间的纠缠交换。利用全光纤商用组件实现了覆盖1.6 THz的相位和频率稳定。这些结果从窄带光子对的集成光子解决方案到独立量子中继器节点间的系统级稳定，解决了现场部署量子中继器的重要挑战。
英文摘要
Promising implementations of first generation quantum repeaters are predicted to require atomic-based quantum memory systems interfaced with photonic sources. Integrated photonics provides a promising solution for fibre-based, field-deployed operation of quantum repeaters, however many leading quantum memory platforms require narrow-bandwidth photons that are challenging to generate with integrated photonics. Narrowband photons also present significant technical challenges when implementing entanglement-swapping, particularly with regards to systems-level stabilisation. This work addresses some of these fundamental and technical challenges, by demonstrating entanglement-swapping using state-of-the-art integrated photon sources with bandwidths compatible with multiple atomic-based quantum memory platforms. We obtained a background-subtracted (net) HOM visibility of 0.99$\,\pm\,$0.01, showing high photon indistinguishability and purity, with a net swapped state visibility of $\mathcal{V}$=0.88$\,\pm\,$0.06 demonstrating that the final entanglement would be sufficient to violate a Bell inequality. The experiment used independent pump lasers for each photon pair source, with highly different frequencies to mimic entanglement swapping between different repeater nodes or platforms. Phase and frequency stabilisation spanning 1.6 THz was achieved using all-fibre, commercially-available components. These results address important challenges in implementing field-deployed quantum repeaters, from the integrated photonic solutions for narrowband photon pairs, to systems-level stabilisation between independent quantum repeater nodes.
Comments11 pages, 4 figures
