Controlling collisional loss and scattering lengths of ultracold dipolar molecules with static electric fields

Abstract

Trapped samples of ultracold molecules are often short-lived, because close collisions between them result in trap loss. We investigate the use of shielding with static electric fields to create repulsive barriers between polar molecules to prevent such loss. Shielding is very effective even for RbCs, with a relatively low dipole moment, and even more effective for molecules such as NaK, NaRb and NaCs, with progressively larger dipoles. Varying the electric field allows substantial control over the scattering length, which will be crucial for the stability or collapse of molecular Bose-Einstein condensates. This arises because the dipole-dipole interaction creates a long-range attraction that is tunable with electric field. For RbCs, the scattering length is positive across the range where shielding is effective, because the repulsion responsible for shielding dominates. For NaK, the scattering length can be tuned across zero to negative values. For NaRb and NaCs, the attraction is strong enough to support tetraatomic bound states, and the scattering length passes through resonant poles where these states cross threshold. For KAg and CsAg, there are multiple bound states and multiple poles. For each molecule, we calculate the variation of scattering length with field and comment on the possibilities for exploring new physics.

arXiv comment12 pages, 8 figures and 1 table

References in corpus (35)

• Feshbach Resonances in Ultracold Gases
• Quantum-State Controlled Chemical Reactions of Ultracold KRb Molecules
• Condensed Matter Theory of Dipolar Quantum Gases
• Creation of ultracold ${}^{87}$RbCs molecules in the rovibrational ground state
• Creation of an ultracold gas of ground-state ${}^{23}{\mathrm{Na}}^{87}\mathrm{Rb}$ molecules
• Calculation of accurate permanent dipole moments of the lowest ${}^{1,3}{\Sigma }^{+}$ states of heteronuclear alkali dimers using extended basis sets
• Tunable Superfluidity and Quantum Magnetism with Ultracold Polar Molecules
• Trapped atomic condensates with anisotropic interactions
• Trapped condensates of atoms with dipole interactions
• Evaporation of microwave-shielded polar molecules to quantum degeneracy
• Ultracold molecules for quantum simulation: rotational coherences in CaF and RbCs
• Microwave shielding of ultracold polar molecules
• Resonant collisional shielding of reactive molecules using electric fields
• Linking Ultracold Polar Molecules
• Feshbach resonances in ultracold atomic and molecular collisions: threshold behaviour and suppression of poles in scattering lengths
• Photo-induced two-body loss of ultracold molecules
• Controlling the scattering length of ultracold dipolar molecules
• Tuning of dipolar interactions and evaporative cooling in a three-dimensional molecular quantum gas
• Suppression of inelastic collisions of polar ${}^1\Sigma$ state molecules in an electrostatic field
• Dipolar Bose-Einstein condensates with dipole-dependent scattering length
• Strongly interacting ultracold polar molecules
• Collisionally Stable Gas of Bosonic Dipolar Ground State Molecules
• Shielding ${}^2\Sigma$ ultracold dipolar molecular collisions with electric fields
• Controlling the Rotational and Hyperfine State of Ultracold ${}^{87}$Rb${}^{133}$Cs Molecules
• Microwave shielding of bosonic NaRb molecules
• Adimensional theory of shielding in ultracold collisions of dipolar rotors
• Tuning ultracold collisions of excited rotational dipolar molecules
• Optical shielding of destructive chemical reactions between ultracold ground-state NaRb molecules
• Long-range interactions between polar alkali-metal diatoms in external electric fields
• Microwave shielding of ultracold polar molecules with imperfectly circular polarization
• High-resolution Internal State Control of Ultracold ${}^{23}$Na${}^{87}$Rb Molecules
• Highly polar molecules consisting of a copper or silver atom interacting with an alkali-metal or alkaline-earth-metal atom
• Electro-association of ultracold dipolar molecules into tetramer field-linked states
• Shielding collisions of ultracold CaF molecules with static electric fields
• Characterizing quasibound states and scattering resonances

Cited by in corpus (5)

• SU(N) magnetism with ultracold molecules
• Three-Body Recombination of Ultracold Microwave-Shielded Polar Molecules
• SU($N$) symmetry with ultracold alkali dimers: weak dependence of scattering properties on hyperfine state
• Thermal behavior of Bose-Einstein condensates of polar molecules
• Strongly dipolar molecular Bose-Einstein condensates: From few- to many-body physics