Spectroscopy of Ultracold, Trapped Cesium Feshbach Molecules

Abstract

We explore the rich internal structure of Cs_2 Feshbach molecules. Pure ultracold molecular samples are prepared in a CO_2-laser trap, and a multitude of weakly bound states is populated by elaborate magnetic-field ramping techniques. Our methods use different Feshbach resonances as input ports and various internal level crossings for controlled state transfer. We populate higher partial-wave states of up to eight units of rotational angular momentum (l-wave states). We investigate the molecular structure by measurements of the magnetic moments for various states. Avoided level crossings between different molecular states are characterized through the changes in magnetic moment and by a Landau-Zener tunneling method. Based on microwave spectroscopy, we present a precise measurement of the magnetic-field dependent binding energy of the weakly bound s-wave state that is responsible for the large background scattering length of Cs. This state is of particular interest because of its quantum-halo character.

15 pages, 12 figures, 4 tables

References in corpus (15)

• Observation of Bose-Einstein Condensation of Molecules
• Repulsively bound atom pairs in an optical lattice
• Pure Gas of Optically Trapped Molecules Created from Fermionic Atoms
• Ultracold heteronuclear molecules in a 3D optical lattice
• Three-body recombination at large scattering lengths in an ultracold atomic gas
• Molecules of Fermionic Atoms in an Optical Lattice
• Observation of molecules produced from a Bose-Einstein condensate
• Formation of Quantum-Degenerate Sodium Molecules
• Preparation of a quantum state with one molecule at each site of an optical lattice
• Radio-Frequency Transitions on Weakly-Bound Ultracold Molecules
• Optimized production of a cesium Bose-Einstein condensate
• Dissociation of ultracold molecules with Feshbach resonances
• `Stückelberg interferometry' with ultracold molecules
• Efficient creation of molecules from a cesium Bose-Einstein condensate
• Spontaneous dissociation of long-range Feshbach molecules

Cited by in corpus (25)

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• Observation of an Efimov-like resonance in ultracold atom-dimer scattering
• Nonadiabatic Landau-Zener-Stückelberg-Majorana transitions, dynamics, and interference
• Amplitude Spectroscopy of a Solid-State Artificial Atom
• Calculations of static dipole polarizabilities of alkali dimers. Prospects for alignment of ultracold molecules
• The hyperfine energy levels of alkali metal dimers: ground-state polar molecules in electric and magnetic fields
• Feshbach resonances, weakly bound molecular states and coupled-channel potentials for cesium at high magnetic fields
• Collisional Properties of p-Wave Feshbach Molecules
• Determination of atomic scattering lengths from measurements of molecular binding energies near Feshbach resonances
• Superfluidity and phase transitions in a resonant Bose gas
• Collisions between tunable halo dimers: exploring an elementary four-body process with identical bosons
• Large-amplitude driving of a superconducting artificial atom: Interferometry, cooling, and amplitude spectroscopy
• Avoided crossings between bound states of ultracold Cesium dimers
• A high phase-space density mixture of ${}^{87}$Rb and ${}^{133}$Cs: towards ultracold heteronuclear molecules
• Resonant atom-dimer collisions in cesium: Testing universality at positive scattering lengths
• Multi-level interference resonances in strongly-driven three-level systems
• Metastable Feshbach Molecules in High Rotational States
• Spatial Landau-Zener-Stückelberg interference in spinor Bose-Einstein condensates
• Optically trapped Feshbach molecules of fermionic 161Dy and 40K
• Repeated output coupling of ultracold Feshbach molecules from a Cs BEC
• Observation of self-oscillating supersonic flow across an acoustic horizon in two dimensions
• Optically trapped Feshbach molecules of fermionic ${}^{161}$Dy and ${}^{40}$K: Role of light-induced and collisional losses
• Observation of high partial-wave Feshbach resonances in ${}^{39}$K Bose-Einstein condensates
• Lifetime of Excitations in Atomic and Molecular Bose-Einstein Condensates
• Observation of modulation-induced Feshbach resonance