Loading and cooling in an optical trap via hyperfine dark states

Year: 2020

Authors: Naik D. S., Eneriz-Imaz H., Carey M., Freegarde T., Minardi F., Battelier B., Bouyer P., Bertoldi A.

Autors Affiliation: Univ Bordeaux, IOGS, CNRS, Lab Photon Numer & Nanosci,UMR 5298, F-33400 Talence, France; Univ Southampton, Sch Phys & Astron, Southampton SO17 1BJ, Hants, England; CNR, Ist Nazl Ott, I-50019 Sesto Fiorentino, Italy; Univ Bologna, Dipartimento Fis & Astron, I-40127 Bologna, Italy

Abstract: We present an optical cooling scheme that relies on hyperfine dark states to enhance loading and cooling atoms inside deep optical dipole traps. We demonstrate a sevenfold increase in the number of atoms loaded in the conservative potential with strongly shifted excited states. In addition, we use the energy selective dark state to efficiently cool the atoms trapped inside the conservative potential rapidly and without losses. Our findings open the door to optically assisted cooling of trapped atoms and molecules which lack the closed cycling transitions normally needed to achieve low temperatures and the high initial densities required for evaporative cooling.

Journal/Review: PHYSICAL REVIEW RESEARCH

Volume: 2 (1)      Pages from:   to:

More Information: We thank L. Ricci for kindly providing a rubidium reservoir in a critical phase of the experiment. This work has been carried out with financial support from the French State, managed by the French National Research Agency (ANR) in the frame of “the Investments for the future” Programme IdEx Bordeaux -LAPHIA (Grant No. ANR-10-IDEX-0302, project OE-TWR), the Horizon 2020 QuantERA ERANET project TAIOL (Grant No. ANR-18-QUAN-00L5-02), the ANR project EOSBECMR (Grant No. ANR-18-CE910003-01), and the Aquitaine Region (projet IASIG3D Grant No. 2015-1R60307-00005207 and project USOFF Grant No. 2018-1R50309). M.C. acknowledges support by Dstl under Contract No. DSTLX-1000097855 and T.F. by the EPSRC through the Quantum Technology Hub for Sensors & Metrology under Grant No. EP/M013294/1.
KeyWords: Coherent population trapping, Cooling and trapping, Dark states
DOI: 10.1103/PhysRevResearch.2.013212