Compression of a cold atomic cloud by on-resonance laser light

Journal of the Optical Society of America B: Optical Physics

Volumn 16, Issue 5, 1999, Pages 702-709

  Khaykovich, Lev ^a   Davidson, Nir ^a  

^a WEIZMANN INSTITUTE OF SCIENCE   (Israel)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0033426031     PISSN: 07403224     EISSN: None     Source Type: Journal    
DOI: 10.1364/JOSAB.16.000702     Document Type: Article

References (23)

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10. These changes also affect the spring constant, as shown by A. Steane, M. Chowdhury, and C. Foot, "Radiation force in the magneto-optical trap," J. Opt. Soc. Am. B 9, 2142 (1992).
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12. See, for instance, evaporative cooling in N. Masuhara, J. M. Doyle, J. C. Sandberg, D. Kleppner, T. J. Greytak, H. F. Hess, and G. P. Kochanski, "Evaporative cooling of spinpolarized atomic hydrogen," Phys. Rev. Lett. 61, 935 (1988), or Raman cooling in H. J. Lee, C. S. Adams, M. Kasevich, and S. Chu, "Raman cooling of atoms in an optical dipole trap," Phys. Rev. Lett. 76, 2658 (1996).
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15. sat despite different experimental situations. 15. We assume a uniform spatial distribution of the atoms over the period of the standing wave. This is applicable to the on-resonance case (δ= 0), whereas at δ ≠ 0 some localization of the atoms toward the nodes (δ > 0) and the antinodes ( δ < 0) of the standing wave is expected owing to the dipole force. We neglect this localization here.
16. A. Fioretti, A. F. Molisch, J. H. Müller, P. Verkerk, and M. Allegrini, "Observation of radiation trapping in a dense Cs magneto-optical trap," Opt. Commun. 149, 415 (1998).
17. At low intensities the neglect of the repulsive inter-atomic forces by our simplified model is not justified anyway.
18. average, we extended the simulations to a two-dimensional Gaussian density distribution n(x, y, z = 0), and the one-dimensional integrated density was defined as ∫n(x, y, z = 0)dy, corresponding to our imaging fluorescence measurements that are described below.
19. P. D. Lett, R. N. Watts, C. I. Westbrook, W. D. Phillips, P. L. Gould, and H. J. Metcalf, "Observation of atoms laser cooled below the Doppler limit," Phys. Rev. Lett. 61, 169 (1988).
20. We observed nearly identical dependence on laser detuning in one-beam and six-beam configurations.
21. Note that for the pulsed compression the optimal compression was obtained for detuning of 1-2 MHz above resonance (see inset of Fig. 7). This frequency shift can be explained by the fact that when the atoms are accelerated during the ∼100-μs compression pulses they acquire a negative Doppler shift of a few megahertz, so their average detuning is close to zero when their initial detuning is somewhat positive. This does not apply for the quasi steady state of Fig. 9, as is confirmed by the exact zero location of the optimal detuning.
22. D. Boiron, A. Michaud, J. M. Fournier, L. Simard, M. Sprenger, G. Grinberg, and C. Salomon, "Cold and dense cesium clouds in far-detuned dipole traps," Phys. Rev. A 57, R4106 (1998).
23. L. Khaykovich, N. Friedman, and N. Davidson, "Saturation of the weak probe amplification in a strongly driven cold and dense atomic cloud," Europhys. J. (to be published).