Experimental realization of ultracold Yb-$^{7}{\rm Li}$ mixtures in mixed dimensions

TL;DR

This paper reports the experimental creation of ultracold Yb-Li mixtures in mixed dimensions using optical lattices, revealing their band structures and scattering properties, and exploring their potential for topological superfluidity.

Contribution

It demonstrates the first realization of ultracold Yb-Li mixtures in mixed dimensions with detailed spectroscopic and scattering measurements.

Findings

Yb-Li mixtures successfully loaded into 3D and 1D optical lattices.

Reconstruction of Yb-173 band structure in presence of Li.

Determination of inter-species scattering lengths.

Abstract

We report on the experimental realization of ultracold $^{174}{\rm Yb}$-$^{7}{\rm Li}$ (Boson-Boson) and $^{173}{\rm Yb}$-$^{7}{\rm Li}$ (Fermion-Boson) mixtures. They are loaded into three dimensional (3D) or one dimensional (1D) optical lattices that are species-selectively deep for the heavy Ytterbium (Yb) and shallow for the light bosonic Lithium (Li) component, realizing novel mixed dimensional systems. In the 1D optical lattice the band structure of $^{173}{\rm Yb}$ is reconstructed in the presence of $^{7}{\rm Li}$. Spectroscopic measurements of the $^{174}{\rm Yb}$-$^{7}{\rm Li}$ mixture in the 3D lattice give access to the $^{174}{\rm Yb}$ Mott-insulator structure. Ground state inter-species scattering lengths are determined to be $|a_{\rm bg}(^{174}{\rm Yb}$-$^{7}{\rm Li})|=(1.11 \pm 0.17)~{\rm nm}$ and $|a_{\rm bg}(^{173}{\rm Yb}$-$^{7}{\rm Li})|=(1.16 \pm 0.18)~{\rm nm}$. The formation and characterization of an ultracold $^{173}{\rm Yb}$-$^{7}{\rm Li}$ mixture is a first step towards a possible realization of a topological $p_x + i\,p_y$ superfluid in this system.