Resonant atom-dimer collisions in cesium: Testing universality at positive scattering lengths
Abstract
We study the collisional properties of an ultracold mixture of cesium atoms and dimers close to a Feshbach resonance near 550G in the regime of positive -wave scattering lengths. We observe an atom-dimer loss resonance that is related to Efimov's scenario of trimer states. The resonance is found at a value of the scattering length that is different from a previous observation at low magnetic fields. This indicates non-universal behavior of the Efimov spectrum for positive scattering lengths. We compare our observations with predictions from effective field theory and with a recent model based on the van der Waals interaction. We present additional measurements on pure atomic samples in order to check for the presence of a resonant loss feature related to an avalanche effect as suggested by observations in other atomic species. We could not confirm the presence of such a feature.
Keywords
Cite
@article{arxiv.1406.3443,
title = {Resonant atom-dimer collisions in cesium: Testing universality at positive scattering lengths},
author = {Alessandro Zenesini and Bo Huang and Martin Berninger and Hanns-Christoph Nägerl and Francesca Ferlaino and Rudolf Grimm},
journal= {arXiv preprint arXiv:1406.3443},
year = {2014}
}