Tuning of dipolar interactions and evaporative cooling in a three-dimensional molecular quantum gas

• URL: http://arxiv.org/abs/2103.06246v2
• Date: Fri, 17 Sep 2021 03:06:24 GMT
• Title: Tuning of dipolar interactions and evaporative cooling in a three-dimensional molecular quantum gas
• Authors: Jun-Ru Li, William G. Tobias, Kyle Matsuda, Calder Miller, Giacomo Valtolina, Luigi De Marco, Reuben R. W. Wang, Lucas Lassabli\`ere, Goulven Qu\'em\'ener, John L. Bohn, Jun Ye
• Abstract summary: We demonstrate tunable elastic dipolar interactions in a bulk gas of ultracold 40K87Rb molecules in 3D. This improvement in the ratio of elastic to inelastic collisions enables direct thermalization. We achieve evaporative cooling mediated by the dipolar interactions in three dimensions.
• Score: 2.409938612878261
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Ultracold polar molecules possess long-range, anisotropic, and tunable dipolar interactions, providing the opportunities to probe quantum phenomena inaccessible with existing cold gas platforms. However, experimental progress has been hindered by the dominance of two-body loss over elastic interactions, which prevents efficient evaporative cooling. Though recent work has demonstrated controlled interactions by confining molecules to a two-dimensional geometry, a general approach for tuning molecular interactions in a three-dimensional (3D), stable system has been lacking. Here, we demonstrate tunable elastic dipolar interactions in a bulk gas of ultracold 40K87Rb molecules in 3D, facilitated by an electric field-induced shielding resonance which suppresses the reactive loss by a factor of thirty. This improvement in the ratio of elastic to inelastic collisions enables direct thermalization. The thermalization rate depends on the angle between the collisional axis and the dipole orientation controlled by an external electric field, a direct manifestation of the anisotropic dipolar interaction. We achieve evaporative cooling mediated by the dipolar interactions in three dimensions. This work demonstrates full control of a long-lived bulk quantum gas system with tunable long-range interactions, paving the way for the study of collective quantum many-body physics.

Related papers

• Nonlocal thermoelectric detection of interaction and correlations in edge states [62.997667081978825]
  We propose the nonlocal thermoelectric response as a direct indicator of the presence of interactions, nonthermal states and the effect of correlations. A setup with two controllable quantum point contacts allows thermoelectricity to monitor the interacting system thermalisation.
  arXiv  Detail & Related papers  (2023-07-18T16:28:59Z)
• Unraveling a cavity induced molecular polarization mechanism from collective vibrational strong coupling [0.0]
  We show that collective vibrational strong coupling of molecules in thermal equilibrium can give rise to significant local electronic polarizations in the thermodynamic limit. Our findings suggest that the thorough understanding of polaritonic chemistry, requires a self-consistent treatment of dressed electronic structure.
  arXiv  Detail & Related papers  (2023-06-09T16:18:51Z)
• Purcell-induced suppression of superradiance for molecular overlayers on noble atom surfaces [0.0]
  We study the impact of an environment on the electromagnetic responses of a molecule in the presence of a dielectric medium. We predict excitation lifetimes of single and few molecules attached to a dielectric surface by knowing the entire quantum-mechanical properties of the molecules.
  arXiv  Detail & Related papers  (2022-11-03T08:53:13Z)
• Tuning long-range fermion-mediated interactions in cold-atom quantum simulators [68.8204255655161]
  Engineering long-range interactions in cold-atom quantum simulators can lead to exotic quantum many-body behavior. Here, we propose several tuning knobs, accessible in current experimental platforms, that allow to further control the range and shape of the mediated interactions.
  arXiv  Detail & Related papers  (2022-03-31T13:32:12Z)
• Evaporation of microwave-shielded polar molecules to quantum degeneracy [1.8133492406483585]
  We demonstrate cooling of a three-dimensional gas of fermionic sodium-potassium molecules to well below the Fermi temperature using microwave shielding. The molecules are protected from reaching short range with a repulsive barrier engineered by coupling rotational states with a blue-detuned circularly polarized microwave. This large elastic-to-inelastic collision ratio allows us to cool the molecular gas down to 21 nanokelvin, corresponding to 0.36 times the Fermi temperature.
  arXiv  Detail & Related papers  (2022-01-13T18:53:27Z)
• Molecular Interactions Induced by a Static Electric Field in Quantum Mechanics and Quantum Electrodynamics [68.98428372162448]
  We study the interaction between two neutral atoms or molecules subject to a uniform static electric field. Our focus is to understand the interplay between leading contributions to field-induced electrostatics/polarization and dispersion interactions.
  arXiv  Detail & Related papers  (2021-03-30T14:45:30Z)
• Resonant enhancement of three-body loss between strongly interacting photons [47.30557822621873]
  Rydberg polaritons provide an example of a rare type of system where three-body interactions can be as strong or even stronger than two-body interactions. We show how the shape and strength of dissipative three-body forces can be universally enhanced for Rydberg polaritons.
  arXiv  Detail & Related papers  (2020-10-19T18:21:49Z)
• Resonant collisional shielding of reactive molecules using electric fields [2.830197032154302]
  We use an external electric field to shift excited collision channels of ultracold molecules into degeneracy with the initial collision channel. Resonant dipolar interactions mix the channels at long range, dramatically altering the intermolecular potential. We realize a long-lived sample of polar molecules in large electric fields.
  arXiv  Detail & Related papers  (2020-09-16T04:24:54Z)
• Dipolar evaporation of reactive molecules to below the Fermi temperature [2.9989215527241453]
  Inelastic losses in molecular collisions have greatly hampered the engineering of low-entropy molecular systems. 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. Direct thermalization among the molecules in the trap leads to efficient dipolar cooling, yielding a rapid increase in phase-space density.
  arXiv  Detail & Related papers  (2020-07-23T22:02:59Z)
• Dynamical Strengthening of Covalent and Non-Covalent Molecular Interactions by Nuclear Quantum Effects at Finite Temperature [58.999762016297865]
  Nuclear quantum effects (NQE) tend to generate delocalized molecular dynamics. NQE often enhance electronic interactions and, in turn, can result in dynamical molecular stabilization at finite temperature. Our findings yield new insights into the versatile role of nuclear quantum fluctuations in molecules and materials.
  arXiv  Detail & Related papers  (2020-06-18T14:30:29Z)
• Optically pumped spin polarization as a probe of many-body thermalization [50.591267188664666]
  We study the spin diffusion dynamics of 13C in diamond, which we dynamically polarize at room temperature via optical spin pumping of engineered color centers. We find good thermal contact throughout the nuclear spin bath, virtually independent of the hyperfine coupling strength. Our results open intriguing opportunities to study the onset of thermalization in a system by controlling the internal interactions within the bath.
  arXiv  Detail & Related papers  (2020-05-01T23:16:33Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.