Abstract The kinetic theory of (2+4)-level atoms in $\sigma^+-\sigma^-$ laser fields is presented. We systemically discuss friction coefficient, momentum diffusion tensor and atomic temperature based on the Fokker--Planck equation. This cooling system is much like that of a (1+3)-level atom, and the temperature is still limited to the Doppler temperature. Since this cooling system has not been investigated before, this work may be regarded as a necessary complement to the laser cooling theory.
Received: 18 July 2008
Revised: 21 April 2009
Accepted manuscript online:
(Calculations and mathematical techniques in atomic and molecular physics)
Fund: Project supported by the National
Fundamental Research Programme of
China (Grants No 2005CB724500).
Cite this article:
Yu Chuang(于闯), Yu De-Shui(于得水), and Chen Jing-Biao(陈景标) Kinetic theory of (2+4)-level atom in $\sigma^+-\sigma^-$ laser fields 2009 Chin. Phys. B 18 3395
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