Probing and Controlling Many-Body Interactions in a Simple Cubic Optical Lattice Clock

We describe recent developments in the operation of an optical atomic clock at unprecedentedly
high atomic densities. Frequency measurements are performed primarily on a band-insulating quantum degenerate Fermi-gas of neutral strontium-87 loaded into a three-dimensional optical lattice with a simple
cubic geometry. Rapid production of such quantum states of matter are enabled by novel techniques in
neutral atom cooling and trapping while precise frequency measurements rely on both state-of-the-art
optical reference cavities and imaging techniques which significantly suppress residual laser phase noise.
The observed frequency shifts about the mHz-wide clock transition are attributable to various manybody
interactions involving Fermi-Hubbard physics and long-range interactions between electric dipoles.
Using accurate models of the observed phenomena, we anticipate both challenging systematic effects and
novel opportunities to generate spin-squeezed states in future generations of atomic clocks operating at
similarly high atomic densities.