Efimov physics: what we can learn from cesium atoms

Cesium is the first species that has revealed signatures of Efimov states and related few-body phenomena. I will first give an overview of the previous observations in this system for purely atomic samples, atom-dimer mixtures, and pure dimer samples, and discuss how all these observations fit together in the Efimov scenario with extensions to four-body systems. I will discuss open question on the interpretation of the results. I will then present our current experiments, which are dedicated to a comparison of Efimov features on different (broad) Feshbach resonances in the same atomic state and to the search for resonant dimer-dimer interactions. Work performed in collaboration with: M. Berninger, F. Ferlaino, W. Harm, J. P. D'Incao, S. Knoop, H.-C. N\"agerl, A. Zenesini.