Miniaturized setups for magneto-optical trapping of ytterbium and strontium

Abstract

Optical lattice clocks based on ytterbium (Yb) and strontium (Sr) are emerging as key technologies in precision timekeeping and metrology. Recent advancements in miniaturization and transportability are making them increasingly accessible for applications outside traditional laboratory settings. However, the degree of miniaturization is limited by the atomic source that is used to provide laser-cooled atoms for the clock spectroscopy. Conventional atomic sources for optical lattice clocks consist of a high-power oven and a magneto-optical trap (MOT) that requires six incident laser beams for three-dimensional trapping and cooling.

Here, we present technologies that allow a significant miniaturization of the required experimental setups to realize a MOT for Yb and Sr. These are a chip-based microstructured atomic oven and in-vacuum optical elements that require only a single incident laser beam to generate all of the required beams for three-dimensional trapping and cooling. The oven was manufactured with LIDE® (laser induced deep etching). It was paired with an aluminum pyramid reflector to load Yb atoms into a MOT. The oven was placed directly at the outside of the reflector, forming a compact setup that is used for atom evaporation and direct trapping and cooling. In this configuration, MOT loading rates above 10^8 atoms/s were measured for oven heating powers below 250 mW. Furthermore, the microstructured oven was paired with a grating MOT chip inside a highly compact vacuum chamber. The chamber was additively manufactured from titanium and the assembled setup spans a volume of less than 750 ml. In this setup, up to 10^5 Sr atoms were trapped in the MOT.