Observation of Efimov Universality across a Nonuniversal Feshbach Resonance in K39

Xie, Xin; Van de Graaff, Michael J.; Chapurin, Roman; Frye, Matthew D.; Hutson, Jeremy M.; D’Incao, José P.; Julienne, Paul S.; Ye, Jun; Cornell, Eric A.

Abstract

We study three-atom inelastic scattering in ultracold 39 K near a Feshbach resonance of intermediate coupling strength. The nonuniversal character of such resonance leads to an abnormally large Efimov absolute length scale and a relatively small effective range r e , allowing the features of the 39 K Efimov spectrum to be better isolated from the short-range physics. Meticulous characterization of and correction for finite-temperature effects ensure high accuracy on the measurements of these features at large-magnitude scattering lengths. For a single Feshbach resonance, we unambiguously locate four distinct features in the Efimov structure. Three of these features form ratios that obey the Efimov universal scaling to within 10%, while the fourth feature, occurring at a value of scattering length closest to r e , instead deviates from the universal value.

Citation

Xie, X., Van de Graaff, M. J., Chapurin, R., Frye, M. D., Hutson, J. M., D’Incao, J. P., …Cornell, E. A. (2020). Observation of Efimov Universality across a Nonuniversal Feshbach Resonance in K39. Physical Review Letters, 125(24), Article 243401. https://doi.org/10.1103/physrevlett.125.243401

• Journal Article Type: Article
• Acceptance Date: Oct 19, 2020
• Online Publication Date: Dec 7, 2020
• Publication Date: Dec 11, 2020
• Deposit Date: Dec 9, 2020
• Publicly Available Date: Sep 30, 2021
• Journal: Physical Review Letters
• Print ISSN: 0031-9007
• Electronic ISSN: 1079-7114
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 125
• Issue: 24
• Article Number: 243401
• DOI: https://doi.org/10.1103/physrevlett.125.243401
• Public URL: https://durham-repository.worktribe.com/output/1283688