Testing Universality of Efimov Physics in an Ultracold Mixture of Lithium and Cesium Atoms

We conduct a survey of Li-Cs-Cs Efimov resonances in a $^6$Li-$^{133}$Cs mixture in the magnetic field range of 800 to 950 G. In this region, limiting our study to the two lowest Zeeman levels of lithium and the lowest Zeeman level of cesium, there are five Feshbach resonances which may be probed. The Cs-Cs scattering length at these resonances varies from -3600 a$_0$ to +1000 a$_0$, allowing us to study the impact of the Cs-Cs scattering length on the Efimov resonance positions. In addition, a combination of broad and narrow Feshbach resonances in this magnetic field range allows us to probe the influence of molecular physics on the Efimov effect, particularly the variation of the three-body parameter.