We present an analytical treatment of the force on a two-level atom interacting with a three-dimensional optical molasses. We show that, for small misalignment of the molasses light fields, corresponding to the so-called supermolasses configuration, there can be a dynamically induced stabilization of the atomic motion. This stabilization increases the time required for the atom to diffuse out of the molasses region and therefore provides a novel explanation of experimental observations. We describe the stabilization effect by analogy with the stabilization of the Kapitza pendulum, which is subject to a harmonic modulation of the pendulum pivot point.We present an analytical treatment of the force on a two-level atom interacting with a three-dimensional optical molasses. We show that, for small misalignment of the molasses light fields, corresponding to the so-called supermolasses configuration, there can be a dynamically induced stabilization of the atomic motion. This stabilization increases the time required for the atom to diffuse out of the molasses region and therefore provides a novel explanation of experimental observations. We describe the stabilization effect by analogy with the stabilization of the Kapitza pendulum, which is subject to a harmonic modulation of the pendulum pivot point.

Optics LettersOct 1, 199410 citations

Influence of optical molasses in loading a shallow optical trap

Mathew Hamilton, Anthony Gorges, Jacob Roberts

We have examined loading of $^{85}\mathrm{Rb}$ atoms into a shallow far-off-resonance trap (FORT) from an optical molasses stage following a magneto-optical trap (MOT) stage and compared it to loading from a MOT stage only. Substantially more atoms could be loaded into the FORT using an optical molasses. To determine why this was the case, we measured the rate of atoms loaded into the FORT and the losses from the FORT during both loading processes over a range of detunings and hyperfine pump powers. We found that the losses induced during MOT loading were essentially the same as the losses induced during molasses loading and decreased with increased red detuning; however, we found that the differences in load rate caused an optical molasses to optimize at a greater detuning, improving the number of atoms we could trap by a factor of 2 over that of optimal loading from a MOT.We have examined loading of $^{85}\mathrm{Rb}$ atoms into a shallow far-off-resonance trap (FORT) from an optical molasses stage following a magneto-optical trap (MOT) stage and compared it to loading from a MOT stage only. Substantially more atoms could be loaded into the FORT using an optical molasses. To determine why this was the case, we measured the rate of atoms loaded into the FORT and the losses from the FORT during both loading processes over a range of detunings and hyperfine pump powers. We found that the losses induced during MOT loading were essentially the same as the losses induced during molasses loading and decreased with increased red detuning; however, we found that the differences in load rate caused an optical molasses to optimize at a greater detuning, improving the number of atoms we could trap by a factor of 2 over that of optimal loading from a MOT.

arXiv:0811.0410Physical Review AJan 21, 20096 citations

Optical molasses, laser traps, and ultracold atoms

Steven Chu

Journal of the Optical Society of America BJan 1, 19870 citations

Optical Molasses

Harold J. Metcalf, P. van der Straten

Graduate texts in contemporary physicsJan 1, 19991 citation

Blue-detuned Magneto-optical Trap of BaF molecules

Zixuan Zeng, Shoukang Yang, Shuhua Deng +1 more

We report the realization of a blue-detuned magneto-optical trap (BDM) of BaF molecules. The (1 + 1) type BDM and (1 + 2) type conveyor-belt MOT are explored. While the (1+1) BDM provides only weak trapping force, the conveyor-belt MOT significantly compresses the molecular cloud, achieving a radius of 320(20) μm, a temperature of 240(60) μK, and a peak density of 1.3{\times}10^7 cm^{-3}, representing a significant improvement over the red MOT. Interestingly, the conveyor-belt MOT of BaF exhibits a large capture velocity, and the loading efficiency from red MOT reaches near unity even without gray molasses. We confirm this by directly loading slowed molecules into the conveyor-belt MOT.We report the realization of a blue-detuned magneto-optical trap (BDM) of BaF molecules. The (1 + 1) type BDM and (1 + 2) type conveyor-belt MOT are explored. While the (1+1) BDM provides only weak trapping force, the conveyor-belt MOT significantly compresses the molecular cloud, achieving a radius of 320(20) μm, a temperature of 240(60) μK, and a peak density of 1.3{\times}10^7 cm^{-3}, representing a significant improvement over the red MOT. Interestingly, the conveyor-belt MOT of BaF exhibits a large capture velocity, and the loading efficiency from red MOT reaches near unity even without gray molasses. We confirm this by directly loading slowed molecules into the conveyor-belt MOT.

arXiv:2506.12892Jun 15, 20251 citation

We have examined loading of

^{85}\mathrm{Rb}

atoms into a shallow far-off-resonance trap (FORT) from an optical molasses stage following a magneto-optical trap (MOT) stage and compared it to loading from a MOT stage only. Substantially more atoms could be loaded into the FORT using an optical molasses. To determine why this was the case, we measured the rate of atoms loaded into the FORT and the losses from the FORT during both loading processes over a range of detunings and hyperfine pump powers. We found that the losses induced during MOT loading were essentially the same as the losses induced during molasses loading and decreased with increased red detuning; however, we found that the differences in load rate caused an optical molasses to optimize at a greater detuning, improving the number of atoms we could trap by a factor of 2 over that of optimal loading from a MOT.