Characterization of a two-color magneto-optical trap for a spin-squeezed optical lattice clock

Abstract

We experimentally realize a magneto-optical trap (MOT) for ytterbium that simultaneously scatters light from two atomic transitions, in order to reduce the minimum magnetic field gradient required for trapping atoms. From the experimental data, we propose a model of the MOT where one transition is responsible for trapping the atoms the other transition is responsible for cooling the atoms. In order to test this model and to better understand the dynamics of this two-color MOT, we perform numerical simulations of the contributions of each transition to the steady-state number of trapped atoms. We then compare the results of the simulations with the experimental results and conclude that the model of the separated trapping and cooling functions is a good model for the two-color MOT. Finally, we examine other elements for which the two-color MOT is possible and derive a condition for the linewidths of the two transitions such that the atoms are trapped.