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Updated: Apr 25, 2026

Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
Tests of universal three-body physics in an ultracold bose-fermi mixture
Ruth S Bloom1, Ming-Guang Hu1, Tyler D Cumby1
1JILA, NIST and University of Colorado, Boulder, Colorado 80309-0440, USA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, USA.
Abstract:
Recent measurements of Efimov resonances for a number of ultracold atom species have revealed an unexpected universality, in which three-body scattering properties are determined by the van der Waals length of the two-body interaction potential. To investigate whether this universality extends to heteronuclear mixtures, we measure loss rate coefficients in an ultracold trapped gas of 40K and 87Rb atoms. We find an Efimov-like resonance in the rate of inelastic collisions between 40K87Rb Feshbach molecules and 87Rb atoms. However, we do not observe any Efimov-related resonances in the rates of inelastic collisions between three atoms. These observations are compared to previous measurements by the LENS group of Efimov resonances in a 41K and 87Rb mixture as well as to recent predictions.
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