A compact Sr magneto-optical trap system for field-deployable optical lattice clocks
Naohiro Okamoto, Takumi Sato, Takatoshi Aoki, Yoshio Torii
Published: 2025/9/17
Abstract
We demonstrate a compact strontium (Sr) magneto-optical trap (MOT) realized in a single vacuum chamber without a Zeeman slower or a two-dimensional MOT. The MOT is directly loaded from a thermal atomic beam generated by an atomic oven. The entire vacuum chamber is maintained by a single ion pump, without employing differential pumping. At an oven temperature of $395\,\mathrm{{}^\circ C}$, the number of atoms in the MOT reaches $10^7$ with a loading rate of $10^7 \,\mathrm{atoms\,s^{-1}}$, while sustaining a background gas pressure in the $10^{-9} \,\mathrm{Torr}$ range. At this oven temperature, the MOT lifetime limited by collisions with background gas is $\sim 5 \,\mathrm{s}$, with the atom number primarily constrained by light-assisted two-body collisions. Our MOT system significantly simplifies the construction of field-deployable optical lattice clocks.