Improvement of spectroscopy resolution has been one of the main drives behind many scientific and technological breakthroughs over the past century, including the invention of the laser and the realization of ultracold atoms. State-of-the-art lasers now maintain optical phase coherence beyond one second and this unprecedented spectral resolving power has been established across the entire visible spectrum and beyond. This new capability in control of light has enabled us to create and probe novel quantum matters via manipulation of dilute atomic and molecular gases at ultralow temperatures. A new generation of optical atomic clocks has been developed, with an uncertainty reaching below 1 x 10-16, surpassing the Cs primary standard. Our latest advance in the Sr optical atomic clock is achieving measurement precision of 1 x 10-17 fractional frequency at a measurement time <1000 s. This unprecedented spectroscopic capability has allowed us to characterize the collision-related systematic effect below 1 x 10-18. It has also enabled us to explore many-body quantum dynamics where seemingly weak atomic interactions give rise to strongly correlated states.
Argonne Physics Division Colloquium Schedule