Magnetically assisted Sisyphus effect

Olivier Emile (1) , Robin Kaiser (2) , Christoph Gerz , Hartmut Wallis , Alain Aspect (3) , Claude Cohen-Tannoudji (2)

1 Département Milieux Divisés
2 LSH-ENS - Laboratoire de Spectroscopie Hertzienne de l'ENS
3 laboratoire Charles Fabry de l'Institut d'Optique / Optique atomique

This paper presents an experimental and theoretical study of laser cooling in a standing wave in the presence of a small transverse magnetic field (Magnetically Assisted Sisyphus Effect: MASE). The analysis is worked out for a Jg=1 to Je=1 transition corresponding to the experiment performed on the $2^{3}\rm S_{1}\longleftrightarrow 2^{3}\rm P_{1}$ transition of metastable helium. In this situation, MASE has an effect opposed to the usual Doppler cooling effect, i.e. it produces heating for a negative detuning. Depending on the various parameters, the competition between MASE and Doppler cooling, which act on different velocity ranges, leads to interesting new effects, such as a bistable force. The velocity dependence of the total force is calculated, using a semi-classical approach. A second theoretical treatment, where the atomic motion is quantized, is used to study the time evolution of the velocity distribution. The results of these calculations are compared to experimental observations.

Domaines: Articles anciens

Olivier Emile, Robin Kaiser, Christoph Gerz, Hartmut Wallis, Alain Aspect, et al.. Magnetically assisted Sisyphus effect. Journal de Physique II, 1993, 3 (12), pp.1709-1733. ⟨10.1051/jp2:1993226⟩. ⟨jpa-00247933⟩