Canadian Journal of Physics

Loading of a far off-resonance dipole force trap for stable 39K

Erika J. Prime, J. A. Behr, M.R. Pearson

Published Jan 1, 2007• 3 citations

Abstract

A useful tool that can achieve a high level of spin polarization is a circularly polarized far off-resonance dipole force trap (CFORT). This work is the first step in its development; building the necessary components to successfully load stable 39K into a linearly polarized far off-resonance trap (FORT) from a magneto-optical trap, where the atoms are precooled to a temperature of 400 μK. The FORT consists of 700 mW of light from a titanium–sapphire ring laser, focused with a 200 mm achromatic lens to a waist of 35 μm. The light is detuned between 1 and 20 nm to the red of the D1 transition and this gives rise to trap depths in the region of a few milliKelvin. A characterization of the FORT's loading efficiency and lifetime as a function of FORT beam detuning, power, and ellipticity are studied. PACS Nos.: 32.80.Pj, 23.40.–s, 39.25.+k

DOI: 10.1139/p07-010

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