Iritani B, Tiberi E, Skomorowski W, Moszynski R, Borkowski M, Zelevinsky T
Department of Physics, Columbia University, 538 West 120th Street, New York, New York 10027-5255, USA.
Centre of New Technologies, University of Warsaw, Banacha 2c, 02-097 Warsaw, Poland.
Phys Rev Lett. 2023 Dec 29;131(26):263201. doi: 10.1103/PhysRevLett.131.263201.
Molecular lattice clocks enable the search for new physics, such as fifth forces or temporal variations of fundamental constants, in a manner complementary to atomic clocks. Blackbody radiation (BBR) is a major contributor to the systematic error budget of conventional atomic clocks and is notoriously difficult to characterize and control. Here, we combine infrared Stark-shift spectroscopy in a molecular lattice clock and modern quantum chemistry methods to characterize the polarizabilities of the Sr_{2} molecule from dc to infrared. Using this description, we determine the static and dynamic blackbody radiation shifts for all possible vibrational clock transitions to the 10^{-16} level. This constitutes an important step toward millihertz-level molecular spectroscopy in Sr_{2} and provides a framework for evaluating BBR shifts in other homonuclear molecules.
分子晶格钟能够以与原子钟互补的方式探寻新物理，比如第五种力或基本常数的时间变化。黑体辐射（BBR）是传统原子钟系统误差预算的主要贡献因素，并且其特性描述和控制极具难度。在此，我们将分子晶格钟中的红外斯塔克位移光谱与现代量子化学方法相结合，以表征Sr₂分子从直流到红外波段的极化率。利用这一描述，我们确定了所有可能的振动钟跃迁到10⁻¹⁶水平的静态和动态黑体辐射位移。这是迈向Sr₂分子毫赫兹级光谱学的重要一步，并为评估其他同核分子中的BBR位移提供了一个框架。
