Trapping of Atoms in Optical Standing Wave Fields

3 Trapping of Atoms in Optical Standing Wave Fields 

The induced dipole force may perhaps be used to trap atoms in a standing wave field [13.17,18]. For a one-dimensional plane standing wave 

Trapping of neutral atoms in a standing light wave, (a) In-duced light pressure force, normalized to the spontaneous force =2hKr as a function of the particle velocity v. (b) One-dimensional oscillation of a trapped particle around the minimum of the potential energy in a plane standing wave 

An estimation of this potential barrier height yields, however, the result, 

The cold atoms may eventually be spatially captured in a three-dimensional standing wave field [13.18]. The motion of the atoms is due to the combined action of spontaneous and induced light pressure. If the light frequency is tuned below resonance, the atoms are cooled by the spontaneous forces until their velocities decrease below the critical value. Due to the induced force they undergo oscillatory motions around the potential minima of the three-dimensional standing wave field. The observation of this motion can be performed with a probe laser, tuned to a transition other than that used for cooling [13.19]. 

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