Beloy K, Hinkley N, Phillips N B, Sherman J A, Schioppo M, Lehman J, Feldman A, Hanssen L M, Oates C W, Ludlow A D
National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA.
National Institute of Standards and Technology, 325 Broadway, Boulder, Colorado 80305, USA and University of Colorado, Department of Physics, Boulder, Colorado 80309, USA.
Phys Rev Lett. 2014 Dec 31;113(26):260801. doi: 10.1103/PhysRevLett.113.260801. Epub 2014 Dec 24.
The Stark shift due to blackbody radiation (BBR) is the key factor limiting the performance of many atomic frequency standards, with the BBR environment inside the clock apparatus being difficult to characterize at a high level of precision. Here we demonstrate an in-vacuum radiation shield that furnishes a uniform, well-characterized BBR environment for the atoms in an ytterbium optical lattice clock. Operated at room temperature, this shield enables specification of the BBR environment to a corresponding fractional clock uncertainty contribution of 5.5×10(-19). Combined with uncertainty in the atomic response, the total uncertainty of the BBR Stark shift is now 1×10(-18). Further operation of the shield at elevated temperatures enables a direct measure of the BBR shift temperature dependence and demonstrates consistency between our evaluated BBR environment and the expected atomic response.
由于黑体辐射（BBR）引起的斯塔克位移是限制许多原子频率标准性能的关键因素，时钟装置内部的BBR环境很难高精度地表征。在此，我们展示了一种真空辐射屏蔽装置，它为镱光学晶格钟中的原子提供了一个均匀的、表征良好的BBR环境。在室温下运行时，这种屏蔽装置能够将BBR环境的规范精确到相应的时钟不确定度贡献为5.5×10^(-19)。结合原子响应的不确定性，BBR斯塔克位移的总不确定度现在为1×10^(-18)。在高温下进一步运行该屏蔽装置能够直接测量BBR位移的温度依赖性，并证明我们评估的BBR环境与预期的原子响应之间的一致性。
