Cooling and trapping of ultracold strontium isotopic mixtures

We present the simultaneous cooling and trapping of an isotopic mixture in a magneto-optical trap and describe the transfer of the mixture into a conservative, far-off-resonant dipole trap. The mixture is prepared with a technique that applies to intermediate and heavy alkaline-earth-metal-like atoms. In this work, ⁸⁸Sr and ⁸⁶Sr are simultaneously loaded first into the magneto-optical trap operated on the ¹S₀-³P₁ spin-forbidden line at 689 nm, and then transferred into the dipole trap. We observe fast interspecies thermalization in the dipole trap which allows one to set a lower bound on the ⁸⁸Sr-⁸⁶Sr elastic cross section.