Quantum metrology with lattice-confined ultracold SR atoms
Quantum state engineering of ultracold matter and precise control of optical fields have together allowed accurate measurement of light-matter interactions for applications in precision tests of fundamental physics. State-of-the-art lasers maintain optical phase coherence over one second. Optical frequency combs distribute this optical phase coherence across the entire visible and infrared parts of the electromagnetic spectrum, leading to the direct visualization and measurement of light ripples. At the same time, ultracold atoms confined in an optical lattice with zero differential ac Stark shift between two clock states allow us to minimize quantum decoherence while strengthening the clock signal. For 87Sr, we achieve a resonance quality factor >2.4 × 1014 on the 1S0 - 3P0 doubly forbidden clock transition at 698 nm [1]. The uncertainty of this new clock has reached 1 × 10-16 and its instability approaches 1 × 10-15 at 1 s [2]. These developments represent a remarkable convergence of ultracold atoms, laser stabilization, and ultrafast science. Further improvements are still tantalizing, with quantum measurement and precision metrology combining forces to explore the next frontier.
