113公里自由空间时间频率传递达到小数点后第19位的不稳定度
113 km Free-Space Time-Frequency Dissemination at the 19th Decimal Instability
AI总结：
本研究开发了高功率频率梳等关键技术，在113公里自由空间链路上实现了$3\times10^{-19}$的残余不稳定度，为全球光学时钟网络和卫星时间频率传递奠定了基础。
摘要：
光学时钟网络在精确导航、“秒”单位的重新定义以及引力测试等多个领域发挥着重要作用。为了建立全球规模的光学时钟网络，必须通过长距离自由空间链路实现稳定度为$10^{-19}$的时间与频率传递。然而，此类尝试此前仅局限于镜面折叠配置下的几十公里范围。在此，我们朝着未来基于卫星的时间频率传递迈出了关键一步。通过开发包括高功率频率梳、高稳定性及高效率的光学收发系统以及高效线性光学采样在内的关键技术，我们演示了在两条独立链路上的自由空间时间频率传递，其时间偏差为飞秒量级，在10,000 s时的残余不稳定度为$3\times10^{-19}$，偏移为$1.6\times10^{-20}\pm 4.3\times10^{-19}$。这种稳定度水平在信道损耗增加至89 dB时仍能保持。我们的工作不仅可直接用于地面应用，也为未来的卫星时间频率传递奠定了坚实基础。
英文摘要：
Optical clock networks play important roles in various fields, such as precise navigation, redefinition of "second" unit, and gravitational tests. To establish a global-scale optical clock network, it is essential to disseminate time and frequency with a stability of $10^{-19}$ over a long-distance free-space link. However, such attempts were limited to dozens of kilometers in mirror-folded configuration. Here, we take a crucial step toward future satellite-based time-frequency disseminations. By developing the key technologies, including high-power frequency combs, high-stability and high-efficiency optical transceiver systems, and efficient linear optical sampling, we demonstrate free-space time-frequency dissemination over two independent links with femtosecond time deviation, $3\times10^{-19}$ at 10,000 s residual instability and $1.6\times10^{-20}\pm 4.3\times10^{-19}$ offset. This level of the stability retains for an increased channel loss up to 89 dB. Our work can not only be directly used in ground-based application, but also firmly laid the groundwork for future satellite time-frequency dissemination.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
