Yin Mo-Juan, Lu Xiao-Tong, Li Ting, Xia Jing-Jing, Wang Tao, Zhang Xue-Feng, Chang Hong
Key Laboratory of Time and Frequency Primary Standards, National Time Service Center, Chinese Academy of Sciences, Xi'an 710600, China.
School of Astronomy and Space Science, University of Chinese Academy of Sciences, Beijing 100049, China.
Phys Rev Lett. 2022 Feb 18;128(7):073603. doi: 10.1103/PhysRevLett.128.073603.
Quantum metrology with ultrahigh precision usually requires atoms prepared in an ultrastable environment with well-defined quantum states. Thus, in optical lattice clock systems deep lattice potentials are used to trap ultracold atoms. However, decoherence, induced by Raman scattering and higher order light shifts, can significantly be reduced if atomic clocks are realized in shallow optical lattices. On the other hand, in such lattices, tunneling among different sites can cause additional dephasing and strongly broadening of the Rabi spectrum. Here, in our experiment, we periodically drive a shallow ^{87}Sr optical lattice clock. Counterintuitively, shaking the system can deform the wide broad spectral line into a sharp peak with 5.4 Hz linewidth. With careful comparison between the theory and experiment, we demonstrate that the Rabi frequency and the Bloch bands can be tuned, simultaneously and independently. Our work not only provides a different idea for quantum metrology, such as building shallow optical lattice clock in outer space, but also paves the way for quantum simulation of new phases of matter by engineering exotic spin orbit couplings.
超高精度的量子计量通常需要在具有明确量子态的超稳定环境中制备原子。因此，在光晶格钟系统中，深晶格势被用于捕获超冷原子。然而，如果在浅光晶格中实现原子钟，由拉曼散射和高阶光频移引起的退相干可以显著降低。另一方面，在这样的晶格中，不同格点之间的隧穿会导致额外的相位失配，并使拉比光谱强烈展宽。在这里，在我们的实验中，我们周期性地驱动一个浅的(^{87}Sr)光晶格钟。与直觉相反，摇晃系统可以将宽的光谱线变形为线宽为(5.4)赫兹的尖锐峰。通过理论与实验的仔细比较，我们证明了拉比频率和布洛赫能带可以同时且独立地被调谐。我们的工作不仅为量子计量提供了一个不同的思路，比如在外层空间构建浅光晶格钟，而且还为通过设计奇异的自旋轨道耦合对新物质相进行量子模拟铺平了道路。
