Two-color Ytterbium MOT in a compact dual-chamber setup

Abstract

We present an experimental scheme for producing ultracold Ytterbium atoms in a compact dual-chamber setup. A dispenser-loaded two-dimensional (2D) magneto-optical trap (MOT) using permanent magnets and operating on the broad $^1S_0\to {}^1P_1$ singlet transition delivers over $10^7$ atoms per second through a differential pumping stage into a three-dimensional (3D) MOT. The two-color 3D MOT uses the broad singlet transition to accumulate $\sim\!2\times 10^7$ atoms of $^{174}\text{Yb}$ within $2.5~\text{s}$ and subsequently the narrow $^1S_0\to {}^3P_1$ intercombination line to cool the atomic cloud to below $10~\mathrm{\mu K}$. We report optimized parameters for each stage of the atom collection sequence, achieving high transfer efficiency. We find that shelving into the triplet state during the broad-transition MOT almost doubles the number of trapped atoms.