Ultracold polar molecules near quantum degeneracy

Abstract

We report the creation and characterization of a near quantum-degenerate gas of polar ${}^{40}$K-${}^{87}$Rb molecules in their absolute rovibrational ground state. Starting from weakly bound heteronuclear KRb Feshbach molecules, we implement precise control of the molecular electronic, vibrational, and rotational degrees of freedom with phase-coherent laser fields. In particular, we coherently transfer these weakly bound molecules across a 125 THz frequency gap in a single step into the absolute rovibrational ground state of the electronic ground potential. Phase coherence between lasers involved in the transfer process is ensured by referencing the lasers to two single components of a phase-stabilized optical frequency comb. Using these methods, we prepare a dense gas of $4\cdot 10^4$ polar molecules at a temperature below 400 nK. This fermionic molecular ensemble is close to quantum degeneracy and can be characterized by a degeneracy parameter of $T/T_F=3$. We have measured the molecular polarizability in an optical dipole trap where the trap lifetime gives clues to interesting ultracold chemical processes. Given the large measured dipole moment of the KRb molecules of 0.5 Debye, the study of quantum degenerate molecular gases interacting via strong dipolar interactions is now within experimental reach.

References in corpus (21)

• A High Phase-Space-Density Gas of Polar Molecules
• Production of cold molecules via magnetically tunable Feshbach resonances
• Optical Production of Ultracold Polar Molecules
• Cold Molecule Spectroscopy for Constraining the Evolution of the Fine Structure Constant
• Ultracold heteronuclear molecules in a 3D optical lattice
• Schemes for robust quantum computation with polar molecules
• Molecules Near Absolute Zero and External Field Control of Atomic and Molecular Dynamics
• Ultracold dense gas of deeply bound heteronuclear molecules
• Photoassociative Production and Trapping of Ultracold KRb Molecules
• Coherent optical transfer of Feshbach molecules to a lower vibrational state
• Magneto-electrostatic trapping of ground state OH molecules
• Calculations of static dipole polarizabilities of alkali dimers. Prospects for alignment of ultracold molecules
• Collisional stability of fermionic Feshbach molecules
• The hyperfine energy levels of alkali metal dimers: ground-state polar molecules in electric and magnetic fields
• Heteronuclear molecules in an optical dipole trap
• Production of cold formaldehyde molecules for study and control of chemical reaction dynamics with hydroxyl radicals
• Suppression of inelastic collisions of polar ${}^1\Sigma$ state molecules in an electrostatic field
• Precise Control of Molecular Dynamics with a Femtosecond Frequency Comb - A Weak Field Route to Strong Field Coherent Control
• Controlling Polar Molecules in Optical Lattices
• Collisional Control of Ground State Polar Molecules and Universal Dipolar Scattering
• Accurate determination of electric-dipole matrix elements in K and Rb from Stark shift measurements

Cited by in corpus (61)

• Controlling the quantum stereodynamics of ultracold bimolecular reactions
• Controlling the hyperfine state of rovibronic ground-state polar molecules
• Trapping ultracold dysprosium: a highly magnetic gas for dipolar physics
• Topological insulators in three dimensions from spontaneous symmetry breaking
• Anisotropic Polarizability of Ultracold Polar ${}^{40}$K${}^{87}$Rb Molecules
• Dipolar Molecules in Optical Lattices
• Out of equilibrium dynamics with Matrix Product States
• Dysprosium magneto-optical traps
• Superfluidity and dimerization in a multilayered system of fermionic polar molecules
• Dispersion interactions and reactive collisions of ultracold polar molecules
• Anisotropic Fermi liquid theory of the ultra cold fermionic polar molecules: Landau parameters and collective modes
• Dipolar Bosons in Triangular Optical Lattices: Quantum Phase Transitions and Anomalous Hysteresis
• Electric field-dependent dynamic polarizability and "magic" conditions for optical trapping of polar molecules
• Simulating quantum magnets with symmetric top molecules
• Polarons in a Dipolar Condensate
• Feshbach spectroscopy and dual-species Bose-Einstein condensation of ${}^{23}\mathrm{Na}-$${}^{39}\mathrm{K}$ mixtures
• Excited states of two-dimensional solitons supported by the spin-orbit coupling and field-induced dipole-dipole repulsion
• Vortices and vortex lattices in quantum ferrofluids
• The Hyperfine Molecular Hubbard Hamiltonian
• Matter-wave solitons supported by field-induced dipole-dipole repulsion with a spatially modulated strength
• Bogoliubov Theory of Dipolar Bose Gas in Weak Random Potential
• Singlet and triplet BCS pairs in a gas of two-species fermionic polar molecules
• Ground-state properties of Dipolar Bose polarons
• Quantum phases of tilted dipolar bosons in two-dimensional optical lattice
• Dipolar Fermi gases in anisotropic traps
• Identification of Deeply Bound Heteronuclear Molecules Using Pulsed Laser Depletion Spectroscopy
• Quantum Hall effects in fast rotating Fermi gases with anisotropic dipolar interaction
• Collective Motion of Polarized Dipolar Fermi Gases in the Hydrodynamic Regime
• Thermodynamic properties of a dipolar Fermi gas
• The J-triplet Cooper pairing with magnetic dipolar interactions
• Exotic Quantum Criticality in One-Dimensional Coupled Dipolar Bosons Tubes
• Ultracold nonreactive molecules in an optical lattice: connecting chemistry to many-body physics
• Evaporative cooling of reactive polar molecules confined in a two-dimensional geometry
• Collective modes of monolayer, bilayer, and multilayer fermionic dipolar liquid
• Critical velocity of flowing supersolids of dipolar Bose gases in optical lattices
• Ultralong-range order in the Fermi-Hubbard model with long-range interactions
• Spin-orbit coupled Fermi liquid theory of ultra-cold magnetic dipolar fermions
• The Molecular Hubbard Hamiltonian: Field Regimes and Molecular Species
• Persistent superfluid flow arising from the He-McKellar-Wilkens effect in molecular dipolar condensates
• Effective three-body interactions for bosons in a double-well confinement
• Microscopic derivation of multi-channel Hubbard models for ultracold nonreactive molecules in an optical lattice
• Multi-channel modeling and two photon coherent transfer paths in NaK
• Quantum optics and frontiers of physics: The third quantum revolution
• Achieving ground-state polar molecular condensates by chainwise atom-molecule adiabatic passage
• Spectroscopy of dipolar fermions in 2D pancakes and 3D lattices
• Dynamical properties of a trapped dipolar Fermi gas at finite temperature
• Interaction-driven Lifshitz transition with dipolar fermions in optical lattices
• Singlet and Triplet Superfluid Competition in a Mixture of Two-Component Fermi and One-Component Dipolar Bose Gases
• Physical dipoles and second order perturbation theory for dipolar fermions in two dimensions
• Pulsed rotating supersonic source used with merged molecular beams
• Second-order interaction corrections to the Fermi surface and the quasiparticle properties of dipolar fermions in three dimensions
• Competing many-body instabilities in two-dimensional dipolar Fermi gases
• External field control of spin-dependent rotational decoherence of ultracold polar molecules
• Efficient production of polar molecular Bose-Einstein condensates via an all-optical R-type atom-molecule adiabatic passage
• Wigner crystal versus Fermionization for one-dimensional Hubbard models with and without long-range interactions
• Fractional quantum Hall states of dipolar fermions in a strained optical lattice
• Superfluid pairing in a mixture of a spin-polarized Fermi gas and a dipolar condensate
• Competing Orders in a Dipolar Bose-Fermi Mixture on a Square Optical Lattice: Mean-Field Perspective
• Many body population trapping in ultracold dipolar gases
• Asymptotic behavior of correlation functions of one-dimensional polar-molecules on optical lattices
• The roton-assisted chiral p-wave superfluid in a quasi-two-dimensional dipolar Bose-Fermi quantum gas mixture