Xin Ming, Şafak Kemal, Peng Michael Y, Kalaydzhyan Aram, Wang Wen-Ting, Mücke Oliver D, Kärtner Franz X
Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron, 22607 Hamburg, Germany.
Department of Physics, University of Hamburg and the Hamburg Center for Ultrafast Imaging, 22761 Hamburg, Germany.
Light Sci Appl. 2017 Jan 13;6(1):e16187. doi: 10.1038/lsa.2016.187. eCollection 2017 Jan.
Synchronous laser-microwave networks delivering attosecond timing precision are highly desirable in many advanced applications, such as geodesy, very-long-baseline interferometry, high-precision navigation and multi-telescope arrays. In particular, rapidly expanding photon-science facilities like X-ray free-electron lasers and intense laser beamlines require system-wide attosecond-level synchronization of dozens of optical and microwave signals up to kilometer distances. Once equipped with such precision, these facilities will initiate radically new science by shedding light on molecular and atomic processes happening on the attosecond timescale, such as intramolecular charge transfer, Auger processes and their impacts on X-ray imaging. Here we present for the first time a complete synchronous laser-microwave network with attosecond precision, which is achieved through new metrological devices and careful balancing of fiber nonlinearities and fundamental noise contributions. We demonstrate timing stabilization of a 4.7-km fiber network and remote optical-optical synchronization across a 3.5-km fiber link with an overall timing jitter of 580 and 680 attoseconds root-mean-square, respectively, for over 40 h. Ultimately, we realize a complete laser-microwave network with 950-attosecond timing jitter for 18 h. This work can enable next-generation attosecond photon-science facilities to revolutionize many research fields from structural biology to material science and chemistry to fundamental physics.
在许多先进应用中，如大地测量、甚长基线干涉测量、高精度导航和多望远镜阵列，具有阿秒级定时精度的同步激光 - 微波网络是非常理想的。特别是，像X射线自由电子激光和强激光束线这样迅速发展的光子科学设施，需要在长达数公里的范围内对数十个光学和微波信号进行全系统的阿秒级同步。一旦具备这种精度，这些设施将通过揭示在阿秒时间尺度上发生的分子和原子过程，如分子内电荷转移、俄歇过程及其对X射线成像的影响，开启全新的科学领域。在此，我们首次展示了一个具有阿秒精度的完整同步激光 - 微波网络，这是通过新型计量装置以及对光纤非线性和基本噪声贡献的精心平衡实现的。我们展示了一个4.7公里光纤网络的定时稳定性，以及跨越3.5公里光纤链路的远程光 - 光同步，在超过40小时的时间里，整体定时抖动的均方根分别为580和680阿秒。最终，我们实现了一个完整的激光 - 微波网络，其定时抖动为950阿秒，持续时间为18小时。这项工作能够使下一代阿秒光子科学设施彻底改变从结构生物学到材料科学、化学再到基础物理学等许多研究领域。
