Magnetooptical trapping

A material increase in the atomic density has been attained in what is known as the dark MOT, wherein the localized atoms are optically pumped to a hyperfine-structure sublevel at which they are off resonance with the main localizing laser field. This method was successfully used to localize sodium atoms by Ketterle et al. (1993). These authors demonstrated a substantial improvement of the trap parameters in comparison with the standard MOT the atomic density amounted to 10 atoms/cm with a large total number of localized atoms (over 10 °). In recent years, the MOT has become the most popular trap for cold atoms. To date, there is a very impressive list 

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A technique that traps single atoms in a magnetooptical trap and are dropped through a high-finesse optical cavity. A laser probe measures atomic motions. 

An ensemble of cold Rydberg atoms is easily obtained after laser excitation of a cold atomic cloud, as those performed in a Gs or lib vapor-cell magnetooptical trap, at a temperature of 135 /jK or 300 fiK respectively. In the case of cesium (for the experiments performed at Laboratoire Aime Cotton) or rubidium (for the experiment performed at the University of Virginia), the atoms p-excited by the cooling lasers are Rydberg-excited by using a laser pulse provided by a dye laser pumped by the third harmonic of a Nd YAG laser... 

Bardou P, Emile O, Courty J-M, Westbrook Cl, Aspect A. (1992) Magnetooptical trapping of metastable helium Collisions in the presence of resonant light. Europhys. Lett. 20 681-686. 

Fig. 6.10 Schemes of one-dimensional (a) and three-dimensional (b) magnetooptical trapping of atoms by two counterpropagating laser beams (a) or three pairs of counterpropagating laser beams (b) with circular polarizations and a. ...

An experiment by the scheme illustrated in Fig. 8.7 was carried out with molecules by Nikolov et al. (1999) using a magnetooptical trap. In this experiment, the trapped laser-cooled potassium atoms were photoassociated to u = 191 ofthe... 

Honda, K., Takahashi, Y., Kuwamoto, T., Fujimoto, M., Toyoda, K. (1999). Magnetooptical trapping of Yb atoms and a limit of the branching ratio of the Pi state. Physical Review A, 59, R934-937. 

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