Quantum state engineering of ultracold matter and precise control of optical fields have allowed accurate measurement of light-matter interactions for applications ranging from precision tests of fundamental physics to quantum information science. State-of-the-art lasers now maintain optical phase coherence over one second. Optical frequency combs distribute this phase coherence across the entire visible and infrared parts of the electromagnetic spectrum, leading to direct visualization and measurement of light ripples. A new generation of light-based atomic clocks has been developed, with ultracold Sr atoms confined in an engineered optical lattice offering unprecedented coherence times for light-matter interactions. The uncertainty of this new clock has reached 1 x 10-16, a factor of 4 below the current best Cs primary standard. These developments represent a remarkable convergence of ultracold matter, laser technology, and ultrafast science. Further improvements are tantalizing, where quantum correlations and measurement protocols will enable explorations of the next frontiers in precision metrology and quantum information science.

Physics Bldg., room 401