Formation of ultracold molecules induced by a high-power single-frequency fiber laser.

The influence of a high-power single-frequency fiber laser on the formation of ultracold ⁸⁵Rb₂ molecules is investigated as a function of its frequency (in the 1062–1070 nm range) in a magneto-optical trap. We find evidence for the formation of ground-state ⁸⁵Rb₂ molecules in low vibrational levels () with a maximal rate of 10⁴ s⁻¹, induced by short-range photoassociation by the fiber laser followed by spontaneous emission. When this laser is used to set up a dipole trap, we measure an atomic loss rate at a wavelength far from the PA resonances, only four times smaller than that observed at a PA resonance wavelength. This work may have important consequences for atom trapping using lasers around the conventional 1064 nm wavelength. [ABSTRACT FROM AUTHOR]