Dipolar evaporation of reactive molecules to below the Fermi temperature

Abstract

Molecules are the building blocks of matter and their control is key to the investigation of new quantum phases, where rich degrees of freedom can be used to encode information and strong interactions can be precisely tuned. Inelastic losses in molecular collisions, however, have greatly hampered the engineering of low-entropy molecular systems. So far, the only quantum degenerate gas of molecules has been created via association of two highly degenerate atomic gases. Here, we use an external electric field along with optical lattice confinement to create a two-dimensional (2D) Fermi gas of spin-polarized potassium-rubidium (KRb) polar molecules, where elastic, tunable dipolar interactions dominate over all inelastic processes. Direct thermalization among the molecules in the trap leads to efficient dipolar evaporative cooling, yielding a rapid increase in phase-space density. At the onset of quantum degeneracy, we observe the effects of Fermi statistics on the thermodynamics of the molecular gas. These results demonstrate a general strategy for achieving quantum degeneracy in dipolar molecular gases to explore strongly interacting many-body phases.

8+4 pages, 4+4 figures

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Cited by in corpus (74)

• Dipolar physics: A review of experiments with magnetic quantum gases
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• Observation of Bose-Einstein Condensation of Dipolar Molecules
• Assembly of a rovibrational ground state molecule in an optical tweezer
• Resonant collisional shielding of reactive molecules using electric fields
• Quantum state manipulation and cooling of ultracold molecules
• Tuning of dipolar interactions and evaporative cooling in a three-dimensional molecular quantum gas
• Bimolecular chemistry in the ultracold regime
• Pattern Formation in Quantum Ferrofluids: from Supersolids to Superglasses
• Laser cooled molecules
• Transition from a polaronic condensate to a degenerate Fermi gas of heteronuclear molecules
• Collisions of ultracold molecules in bright and dark optical dipole traps
• Self-bound dipolar droplets and supersolids in molecular Bose-Einstein condensates
• Collisionally Stable Gas of Bosonic Dipolar Ground State Molecules
• Tunable itinerant spin dynamics with polar molecules
• Ultracold Gas of Dipolar NaCs Ground State Molecules
• Ultracold Sticky Collisions: Theoretical and Experimental Status
• Laser cooling for quantum gases
• Collisions Between Ultracold Molecules and Atoms in a Magnetic Trap
• Microwave shielding of bosonic NaRb molecules
• High Phase-Space Density of Laser-Cooled Molecules in an Optical Lattice
• Polarization Enhanced Deep Optical Dipole Trapping of $\Lambda$-cooled Polar Molecules
• Evidence for association of triatomic molecule in ultracold ${}^{23}$Na${}^{40}$K and ${}^{40}$K mixture
• Quantum mixtures of ultracold gases of neutral atoms
• Reactions Between Layer-Resolved Molecules Mediated by Dipolar Exchange
• Blue-Detuned Magneto-Optical Trap of Molecules
• Dynamical generation of spin squeezing in ultra-cold dipolar molecules
• Optical cycling of AlF molecules
• Magnetic Feshbach resonances in collisions of ${}^{23}$Na${}^{40}$K with ${}^{40}$K
• Diatomic molecules of alkali-metal and alkaline-earth-metal atoms: interaction potentials, dipole moments, and polarizabilities
• Effective potential and superfluidity of microwave-dressed polar molecules
• Seconds-scale coherence on nuclear spin transitions of ultracold polar molecules in 3D optical lattices
• Observation of generalized t-J spin dynamics with tunable dipolar interactions
• Accurate determination of the scattering length of erbium atoms
• Towards improved loading, cooling, and trapping of molecules in magneto-optical traps
• Collisional losses of ultracold molecules due to intermediate complex formation
• Double Microwave Shielding
• Electro-association of ultracold dipolar molecules into tetramer field-linked states
• Ultracold LiCr: a new pathway to quantum gases of paramagnetic polar molecules
• Preparation of a quantum degenerate mixture of ${}^{23}$Na${}^{40}$K molecules and ${}^{40}$K atoms
• Atomic Quantum Technologies for Quantum Matter and Fundamental Physics Applications
• SU(N) magnetism with ultracold molecules
• Four-body singlet potential energy surface for reactions of calcium monofluoride
• Rotational-state dependence of interactions between polar molecules
• Observation of Microwave Shielding of Ultracold Molecules
• A general approach to state-dependent optical tweezer traps for polar molecules
• Symmetry breaking in sticky collisions between ultracold molecules
• Thermoviscous Hydrodynamics in Non-Degenerate Dipolar Bose Gases
• Can the dipolar interaction suppress dipolar relaxation?
• High-fidelity imaging of a band insulator in a three-dimensional optical lattice clock
• Collisions of Spin-polarized YO Molecules for Single Partial Waves
• Anisotropic acoustics in dipolar Fermi gases
• A ship-in-a-bottle quantum gas microscope setup for magnetic mixtures
• Momentum-selective pair creation of spin excitations in dipolar bilayers
• Ultracold Interactions between Ions and Polar Molecules
• An Electro-Optical Trap for Polar Molecules
• Synthetic Mutual Gauge Field in Microwave-Shielded Polar Molecular Gases
• Rotational properties of two interacting cold polar molecules: linear, symmetric, and asymmetric tops
• Effective potential and scattering length of shielding polar molecules
• Quenched Magneto-association of Ultracold Feshbach Molecules
• Genetics-based deperturbation analysis for the spin-orbit coupled ${\mathrm{A}}^1{\Sigma }^{+}$ and ${\mathrm{b}}^3{\Pi }_{0^{+}}$ states of LiRb
• Broad Feshbach resonance with a large background scattering length in a fermionic atom-molecule mixture
• Multiple polaron quasiparticles with dipolar fermions in a bilayer geometry
• Ultracold coherent control of molecular collisions at a Förster resonance
• Ground-state selection via many-body superradiant decay
• Propagation of light in cold emitter ensembles with quantum position correlations due to static long-range dipolar interactions
• Metastable ferromagnetic clusters in dissipative many-body systems of polar molecules
• Strongly dipolar molecular Bose-Einstein condensates: From few- to many-body physics
• Hyperfine van der Waals repulsion between open-shell polar molecules
• Analogue Black Holes in Reactive Molecules
• Ultracold high-spin $\Sigma$-state polar molecules for new physics searches
• Trion formation and ordering in the attractive SU(3) Fermi-Hubbard model
• Preparation of quasi-two-dimensional Bose mixture of ultracold ${}^{23}$Na and ${}^{87}$Rb atoms