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Quantum Matter Seminar

Monday, April 3, 2023
4:00pm to 5:00pm
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East Bridge 114
Quantum science with alkaline-earth atoms: from simulating orbital physics to spin-squeezed optical clocks
Nelson Darkwah Oppong, Department of Physics, JILA, University of Colorado at Boulder,

Over the last decade, alkaline-earth(-like) atoms such as strontium and ytterbium have become powerful workhorses in quantum science. Their growing prevalence is due to atomic properties favorable for performing precision measurements, simulating electrons in solids, or storing quantum information. In this talk, I will highlight two such applications in the context of quantum simulations and optical atomic clocks.

First, I discuss a recent study of non-equilibrium dynamics in a cold-atom analog of the mass-imbalanced Fermi-Hubbard model. In this system, ytterbium atoms in the ground and clock state mimic heavy and light particles hopping on a lattice. Harnessing precise control over their interactions, we reveal a regime with unusually slow dynamics and a connection to interacting systems that evade ergodicity.

Second, I discuss our recent work on spin-squeezing in a programmable optical atomic clock. By employing single-atom control and read-out of strontium atoms, we characterize how finite-range Rydberg interactions can generate entanglement on the clock transition. Using the resulting spin-squeezed states in a differential clock comparison, we demonstrate an optical-clock stability of up to 3.5 dB below the standard quantum limit.