An Experimental Platform for Studying the Heteronuclear Efimov Effect with an Ultracold Mixture of \(^\textbf{6}\)Li and \(^\textbf{133}\)Cs Atoms

We present the experimental apparatus enabling the observation of the heteronuclear Efimov effect in an optically trapped ultracold mixture of \(^6\) $_{}^6$ Li- \(^{133}\) $_{}^{133}$ Cs with high-resolution control of the interactions. A compact double-species Zeeman slower consisting of four interleaving helical coils allows for a fast-switching between two optimized configurations for either Li or Cs and provides an efficient sequential loading into their respective MOTs. By means of a bichromatic optical trapping scheme based on species-selective trapping we prepare mixtures down to 100 nK of \({1\times 10^{4}}\) $1\times {10}^4$ Cs atoms and \({7\times 10^{3}}\) $7\times {10}^3$ Li atoms. Highly stable magnetic fields allow high-resolution atom-loss spectroscopy and enable to resolve splitting in the loss feature of a few tens of milligauss. These features allowed for a detailed study of the Efimov effect.