Thermalization and Sub-Poissonian Density Fluctuations in a Degenerate Molecular Fermi Gas.

  title={Thermalization and Sub-Poissonian Density Fluctuations in a Degenerate Molecular Fermi Gas.},
  author={William G. Tobias and Kyle Matsuda and Giacomo Valtolina and Luigi De Marco and Jun-Ru Li and Jun Ye},
  journal={Physical review letters},
  volume={124 3},
We observe thermalization in the production of a degenerate Fermi gas of polar ^{40}K^{87}Rb molecules. By measuring the atom-dimer elastic scattering cross section near the Feshbach resonance, we show that Feshbach molecules rapidly reach thermal equilibrium with both parent atomic species. Equilibrium is essentially maintained through coherent transfer to the ground state. Sub-Poissonian density fluctuations in Feshbach and ground-state molecules are measured, giving an independent… 
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1JILA, National Institute of Standards and Technology and Department of Physics, University of Colorado, Boulder, CO, USA. 2Université ParisSaclay, CNRS, Laboratoire Aimé Cotton, Orsay, France.
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