Optical tweezer arrays of strontium atoms

Abstract

This thesis presents the development of a strontium optical tweezer array apparatus for precision measurements, towards a spin squeezed tweezer array clock. We demonstrate fast single atom detection of strontium atoms in a tweezer in just , with fidelity 0.989(6). With the addition of Sisyphus cooling we measure comparable fidelity though with a longer exposure time, and can resolve zero, one, and
two atoms all with fidelity . Holographic magic wavelength tweezer arrays of strontium atoms are constructed, demonstrating loaded arrays of over 20 tweezers. High magnification imaging is used to show site-resolved imaging of atoms in tweezers spaced by as little as , despite aberrations in the design of the objective
lens collecting the fluorescence. The precision measurement and cancellation of the electric field at the location
of the atoms is demonstrated using Rydberg atoms as sensors, measuring the stray electric field to be , before cancelling it to a residual field of
. The demonstrated residual electric field produces an environment compatible with precision measurements, where the residual electric field would
not be limiting on any atomic clock, while also opening a pathway to precision measurements of Rydberg states. Our clock laser is introduced and characterised
against a GPS-referenced difference frequency comb, showing stability compatible with the use as a local oscillator for an atomic clock. We consider plans for the implementation of this clock laser system towards making clock measurements.