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

Abstract

We observe thermalization in the production of a degenerate Fermi gas of polar ${}^{40}\text{K}{}^{87}\text{Rb}$ 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 characterization of degeneracy and directly probing the molecular Fermi--Dirac distribution.

arXiv comment5 pages, 4 figures; supplementary material (6 pages, 5 figures)

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Cited by in corpus (21)

• Evaporation of microwave-shielded polar molecules to quantum degeneracy
• Resonant collisional shielding of reactive molecules using electric fields
• Dipolar evaporation of reactive molecules to below the Fermi temperature
• Sub-Doppler Cooling and Compressed Trapping of YO Molecules at $\mu$K Temperatures
• Tuning of dipolar interactions and evaporative cooling in a three-dimensional molecular quantum gas
• Transition from a polaronic condensate to a degenerate Fermi gas of heteronuclear molecules
• Collisions Between Ultracold Molecules and Atoms in a Magnetic Trap
• Quantum control of molecules for fundamental physics
• Dynamical generation of spin squeezing in ultra-cold dipolar molecules
• Quantum Many-Body Physics with Ultracold Polar Molecules: Nanostructured Potential Barriers and Interactions
• Resonant control of elastic collisions between ${}^{23}$Na${}^{40}$K molecules and ${}^{40}$K atoms
• Preparation of a quantum degenerate mixture of ${}^{23}$Na${}^{40}$K molecules and ${}^{40}$K atoms
• Rotational-state dependence of interactions between polar molecules
• Collisions in a dual-species magneto-optical trap of molecules and atoms
• High-fidelity imaging of a band insulator in a three-dimensional optical lattice clock
• The chemistry of AlF and CaF production in buffer gas sources
• Broad Feshbach resonance with a large background scattering length in a fermionic atom-molecule mixture
• Fate of thermalization of ultracold fermions with two-body dissipation
• Atom-Molecule Superradiance and Entanglement with Cavity-Mediated Three-Body Interactions
• Multiple polaron quasiparticles with dipolar fermions in a bilayer geometry
• Heuristic machinery for thermodynamic studies of SU(N) fermions with neural networks