Experiments with Ultracold Strontium in Compact Grating Magneto-Optical Trap Geometries

Abstract

In this thesis, we present the construction of a new apparatus for conducting experiments withultracold strontium. The new apparatus is designed with a high-flux atomic source, a custom science chamber optimized for optical access, high-current Bitter electromagnets, and an updated computer control system. We discuss in-depth the implementation of an insulated-gate bipolar transistor (IGBT) for fast current control of the magnetic field coils. We also present the design of JQI AutomatioN for Experiments (JANE): a programmable system on chip (PSoC)-based pseudoclock device that we use as the main clocking device for our experiments. Next, we report the realization of the first magneto-optical trap (MOT) of an alkaline-earth atom with a tetrahedral trap geometry produced by a nanofabricated diffraction grating. We have demonstrated a broad-line MOT in bosonic 88Sr and fermionic 87Sr. We trap approximately 4x10^7 atoms of 88Sr and achieve temperatures of around 6 mK, with a trap lifetime of around 1 s. Finally, we demonstrate sawtooth wave adiabatic passage (SWAP) in a narrow-line MOT of 88Sr atoms. In the narrow-line MOT, we trap approximately 3x10^6 atoms, with an average temperature of 3.4 µK and a trap lifetime of 0.77 s. We also discuss the possibility for a narrow- line grating MOT of the fermionic isotope. Our work with strontium grating MOTs is a step in the direction of compact quantum devices with alkaline-earth atoms.