Suppression of Unitary Three-Body Loss in a Degenerate Bose-Fermi Mixture

• Main Authors: Bause, R. (Author), Bloch, I. (Author), Chen, X.-Y (Author), Duda, M. (Author), Luo, X.-Y (Author), Schindewolf, A. (Author)
• Format: Article
• Language: English
• Published: American Physical Society 2022
• Subjects: Bose gas; Bose-Fermi mixtures; Bosons; Degenerate Fermi gas; Electron gas; Fermions; Mixtures; Ruderman-Kittel-Kasuya-Yosida; Scattering length; Temperature scaling; Thermal; Three body; Ultra-cold; Unitarity
• Online Access: View Fulltext in Publisher

 We study three-body loss in an ultracold mixture of a thermal Bose gas and a degenerate Fermi gas. We find that at unitarity, where the interspecies scattering length diverges, the usual inverse-square temperature scaling of the three-body loss found in nondegenerate systems is strongly modified and reduced with the increasing degeneracy of the Fermi gas. While the reduction of loss is qualitatively explained within the few-body scattering framework, a remaining suppression provides evidence for the long-range Ruderman-Kittel-Kasuya-Yosida (RKKY) interactions mediated by fermions between bosons. Our model based on RKKY interactions quantitatively reproduces the data without free parameters, and predicts one order of magnitude reduction of the three-body loss coefficient in the deeply Fermi-degenerate regime. © 2022 authors. Published by the American Physical Society.