论文标题
通过量子频率转换，被困的离子值和780 nm光子之间的纠缠
Entanglement between a trapped ion qubit and a 780-nm photon via quantum frequency conversion
论文作者
论文摘要
未来的量子网络将需要能够以不自然发出的物质量子量的光子频率产生物质纠缠的能力。这允许进行混合网络体系结构，这些光子可以将其与其他工具和量子技术搭配使用，可用于多重，路由和存储等任务，但在与物质Qubit Qubit源的波长不同的情况下运行，同时还减少了网络损失。在这里，我们演示了一个被困的离子和780 nm光子的纠缠，该波长可以与基于中性RB的量子网络设备相互作用。单个钡离子用于产生与离子纠缠的493 nm光子，然后在保留纠缠时将其转换为780 nm。我们生成带有保真度$ \ geq $ 0.93（2）和$ \ geq $ 0.84（2）的离子 - 光子纠缠，分别为493 nm和780 nm的光子，富裕度下降是由于我们在780 nm nm的信号噪声降低而产生的。
Future quantum networks will require the ability to produce matter-photon entanglement at photon frequencies not naturally emitted from the matter qubit. This allows for a hybrid network architecture, where these photons can couple to other tools and quantum technologies useful for tasks such as multiplexing, routing, and storage, but which operate at wavelengths different from that of the matter qubit source, while also reducing network losses. Here, we demonstrate entanglement between a trapped ion and a 780 nm photon, a wavelength which can interact with neutral-Rb-based quantum networking devices. A single barium ion is used to produce 493 nm photons, entangled with the ion, which are then frequency converted to 780 nm while preserving the entanglement. We generate ion-photon entanglement with fidelities $\geq$ 0.93(2) and $\geq$ 0.84(2) for 493 nm and 780 nm photons respectively with the fidelity drop arising predominantly from a reduction in the signal-noise of our detectors at 780 nm compared with at 493 nm.
