Ultracold Sticky Collisions: Theoretical and Experimental Status

Abstract

Collisional complexes, which are formed as intermediate states in molecular collisions, are typically short-lived and decay within picoseconds. However, in ultracold collisions involving bialkali molecules, complexes can live for milliseconds, completely changing the collision dynamics. This can lead to unexpected two-body loss in samples of nonreactive molecules. During the last decade, such "sticky" collisons have been a major hindrance in the preparation of dense and stable molecular samples, especially in the quantum-degenerate regime. Currently, the behavior of the complexes is not fully understood. For example, in some cases their lifetime has been measured to be many orders of magnitude longer than recent models predict. This is not only an intriguing problem in itself but also practically relevant, since understanding molecular complexes may help to mitigate their detrimental effects. Here, we review the recent experimental and theoretical progress in this field. We treat the case of molecule-molecule as well as molecule-atom collisions.

arXiv comment15 pages, 7 figures. Comments and suggestions welcome

References in corpus (70)

• From Quantum Chaos and Eigenstate Thermalization to Statistical Mechanics and Thermodynamics
• A High Phase-Space-Density Gas of Polar Molecules
• Stimulated Raman adiabatic passage in physics, chemistry and beyond
• Condensed Matter Theory of Dipolar Quantum Gases
• Ultracold dense samples of dipolar RbCs molecules in the rovibrational and hyperfine ground state
• Ultracold Dipolar Gas of Fermionic ${}^{23}$Na${}^{40}$K Molecules in their Absolute Ground State
• Creation of ultracold ${}^{87}$RbCs molecules in the rovibrational ground state
• Non-standard Hubbard models in optical lattices: a review
• Creation of an ultracold gas of ground-state ${}^{23}{\mathrm{Na}}^{87}\mathrm{Rb}$ molecules
• Quantum gas of rovibronic ground-state molecules in an optical lattice
• Reactions of ultracold alkali metal dimers
• Quantum phase transition in a two-dimensional system of dipoles
• Universal rate constants for reactive collisions of ultracold molecules
• Long-Lived Ultracold Molecules with Electric and Magnetic Dipole Moments
• Direct observation of bimolecular reactions of ultracold KRb molecules
• Evaporation of microwave-shielded polar molecules to quantum degeneracy
• Observation of magnetically tunable Feshbach resonances in ultracold ${}^{23}$Na${}^{40}$K+${}^{40}$K collisions
• Statistical Aspects of Ultracold Resonant Scattering
• Magnetically-Trapped Molecules Efficiently Loaded from a Molecular MOT
• Assembly of a rovibrational ground state molecule in an optical tweezer
• Anomalous Behavior of Spin Systems with Dipolar Interactions
• Photo-induced two-body loss of ultracold molecules
• Collisions of ultracold ^{23}Na^{87}Rb molecules with controlled chemical reactivities
• Sticky collisions of ultracold RbCs molecules
• Dipolar evaporation of reactive molecules to below the Fermi temperature
• Collisional Cooling of Ultracold Molecules
• Observation of Collisions between Two Ultracold Ground-State CaF Molecules
• Loss of ultracold RbCs molecules via optical excitation of long-lived two-body collision complexes
• Tuning of dipolar interactions and evaporative cooling in a three-dimensional molecular quantum gas
• Microwave traps for cold polar molecules
• Bimolecular chemistry in the ultracold regime
• Precision test of statistical dynamics with state-to-state ultracold chemistry
• Cold N+NH Collisions in a Magnetic Trap
• Laser cooled molecules
• Collisions of ultracold molecules in bright and dark optical dipole traps
• State-to-state control of ultracold molecular reactions
• Self-bound dipolar droplets and supersolids in molecular Bose-Einstein condensates
• Control of reactive collisions by quantum interference
• Probing photoinduced two-body loss of ultracold non-reactive bosonic ${}^{23}$Na${}^{87}$Rb and ${}^{23}$Na${}^{39}$K molecules
• Collisions between cold molecules in a superconducting magnetic trap
• Ultracold Gas of Dipolar NaCs Ground State Molecules
• A quasiclassical method for calculating the density of states of ultracold collision complexes
• Liquid and crystal phase of dipolar fermions in two dimensions
• Long-Lived Complexes, Ergodicity and Chaos in Ultracold Molecular Collisions
• Collisions Between Ultracold Molecules and Atoms in a Magnetic Trap
• Field-linked resonances of polar molecules
• A Feshbach resonance in collisions between ultracold ground state molecules
• Dipolar Collisions of Ultracold Ground-state Bosonic Molecules
• Evidence for association of triatomic molecule in ultracold ${}^{23}$Na${}^{40}$K and ${}^{40}$K mixture
• A new quantum gas apparatus for ultracold mixtures of K and Cs and KCs ground-state molecules
• Long-lived complexes and signatures of chaos in ultracold K2+Rb collisions
• Magnetic Feshbach resonances in collisions of ${}^{23}$Na${}^{40}$K with ${}^{40}$K
• Unified model of ultracold molecular collisions
• Controlling Spin-flips of Molecules in an Electromagnetic Trap
• Efficient conversion of closed-channel dominated Feshbach molecules of ${}^{23}$Na${}^{40}$K to their absolute ground state
• Singlet Pathway to the Ground State of Ultracold Polar Molecules
• Ultracold ${}^{88}{\mathrm{Sr}}_2$ molecules in the absolute ground state
• Liquid crystal phases of two-dimensional dipolar gases and Berezinskii-Kosterlitz-Thouless melting
• Complexes formed in collisions between ultracold alkali-metal diatomic molecules and atoms
• Molecular Collisions: from Near-cold to Ultra-cold
• Collisional losses of ultracold molecules due to intermediate complex formation
• Probing ultracold chemistry using ion spectrometry
• Resonant control of elastic collisions between ${}^{23}$Na${}^{40}$K molecules and ${}^{40}$K atoms
• Observation of resonant dipolar collisions in ultracold ${}^{23}$Na${}^{87}$Rb rotational mixtures
• Supersolidity of a dipolar Fermi gas in a cubic optical lattice
• Microwave trap for atoms and molecules
• Electric field dependence of complex-dominated ultracold molecular collisions
• Hyperfine dependent atom-molecule loss analyzed by the analytic solution of few-body loss equations
• Symmetry breaking in sticky collisions between ultracold molecules
• Magnetic trapping of ultracold molecules at high density

Cited by in corpus (30)

• Collisionally Stable Gas of Bosonic Dipolar Ground State Molecules
• Ultracold Gas of Dipolar NaCs Ground State Molecules
• Ultracold field-linked tetratomic molecules
• Diatomic molecules of alkali-metal and alkaline-earth-metal atoms: interaction potentials, dipole moments, and polarizabilities
• High density loading and collisional loss of laser cooled molecules in an optical trap
• Hyperfine-to-rotational energy transfer in ultracold atom-molecule collisions
• Electro-association of ultracold dipolar molecules into tetramer field-linked states
• Double Microwave Shielding
• Three-Body Recombination of Ultracold Microwave-Shielded Polar Molecules
• Efficient Pathway to NaCs Ground State Molecules
• Laser cooling of a fermionic molecule
• Magnetic Feshbach resonances in ultracold atom-molecule collisions
• Chemical reactions of ultracold alkaline-earth-metal diatomic molecules
• A ship-in-a-bottle quantum gas microscope setup for magnetic mixtures
• Spin Squeezing with Itinerant Dipoles: A Case for Shallow Lattices
• Sticking lifetime of ultracold CaF molecules in triplet interactions
• Dissipative Superfluidity in a Molecular Bose-Einstein Condensate
• Multichannel quantum defect theory with a frame transformation for ultracold atom-molecule collisions in magnetic fields
• Synthetic Mutual Gauge Field in Microwave-Shielded Polar Molecular Gases
• Macroscopic Particle Transport in Dissipative Long-Range Bosonic Systems
• CaF+CaF interactions in the ground and excited electronic states: implications for collisional losses
• Multi-state detection and spatial addressing in a microscope for ultracold molecules
• Narrowline Laser Cooling and Spectroscopy of Molecules via Stark States
• Universality and threshold laws for collision lifetimes at ultralow temperatures
• Efimov Effect in Ultracold Microwave-Shielded Polar Molecules
• Strongly dipolar molecular Bose-Einstein condensates: From few- to many-body physics
• Metastable ferromagnetic clusters in dissipative many-body systems of polar molecules
• A quadratic-scaling algorithm with guaranteed convergence for quantum coupled-channel calculations
• Charge Exchange Dynamics in Cold Collisions of ${}^{40}$CaH${}^{+}$ and ${}^{39}$K
• Stabilization of three-body resonances to bound states in a continuum