Institute for Quantum Information Seminar

Note time change to 4:00 pm.

Optical clocks have revolutionized the science of timekeeping, permitting frequency measurements at (and even below) the level of a part in 1017 systematic uncertainty. Neutral atom optical standards based on ultracold lattice-trapped atoms promise an order of magnitude increase in measurement precision over frequency standards based on single ions, but require the highest levels of laser precision to fully realize this improvement and operate near the limit set by quantum fluctuations. In this seminar, I will introduce alkaline earth atoms in the context of precision frequency measurement and describe the features that make this class of neutral atoms desirable for optical frequency standards. I will then describe the JILA 87Sr optical lattice clock, where thousands of essentially decoherence-free 87Sr atoms are probed by a laser with <30 mHz linewidth. This level of precision allows access to a regime in which quantum fluctuations play a significant role, enabling near quantum-limited clock operation and the study of quantum many-body physics, which I will discuss. Such precise atom-laser interactions should permit direct characterization and manipulation of many-body states and explorations of the SU(N) symmetry exhibited by the nuclear spin of fermionic alkaline earth atoms.