Polarization Enhanced Deep Optical Dipole Trapping of $\mathrm{\ensuremath{\Lambda}}$-Cooled Polar Molecules

Polarization Enhanced Deep Optical Dipole Trapping of $Λ$ -Cooled Polar Molecules

Thomas K. Langin, Varun Jorapur, Yuqi Zhu, Qian Wang, and David DeMille

Phys. Rev. Lett. 127, 163201 – Published 12 October 2021

Abstract

We demonstrate loading of SrF molecules into an optical dipole trap (ODT) via in-trap $Λ$ -enhanced gray molasses cooling. We find that this cooling can be optimized by a proper choice of relative ODT and cooling beam polarizations. In this optimized configuration, we observe molecules with temperatures as low as $14 (1) μ K$ in traps with depths up to $570 μ K$ . With optimized parameters, we transfer $\sim 5 %$ of molecules from our radio-frequency magneto-optical trap into the ODT, at a density of $\sim 2 \times 10^{9} {cm}^{- 3}$ , a phase space density of $\sim 2 \times 10^{- 7}$ , and with a trap lifetime of $\sim 1 s$ .

Received 11 June 2021
Revised 12 August 2021
Accepted 9 September 2021

DOI:https://doi.org/10.1103/PhysRevLett.127.163201

Physics Subject Headings (PhySH)

Cold and ultracold molecules Cooling & trapping Molecule trapping & guiding Optical lattices & traps

Atomic, Molecular & Optical

Authors & Affiliations

Thomas K. Langin ^1,2, Varun Jorapur ^1,2, Yuqi Zhu^1,2, Qian Wang ^1,2, and David DeMille³

¹Department of Physics, Yale University, New Haven, Connecticut, Connecticut 06520, USA
²Yale Quantum Institute, Yale University, New Haven, Connecticut 06520, USA
³Department of Physics, University of Chicago, Chicago, Illinois 60637, USA