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Dynamical Cooling of Trapped Gases I: One Atom Problem

Luis Santos·Maciej Lewenstein
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Abstract

We study the laser cooling of one atom in an harmonic trap beyond the Lamb-Dicke regime. By using sequences of laser pulses of different detunings we show that the atom can be confined into just one state of the trap, either the ground state or an excited state of the harmonic potential. The last can be achieved because under certain conditions an excited state becomes a dark state. We study the problem in one and two dimensions. For the latter case a new cooling mechanism is possible, based on the destructive interference between the effects of laser fields in different directions, which allows the creation of variety of dark states. For both, one and two dimensional cases, Monte Carlo simulations of the cooling dynamics are presented.

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Luis Santos, Maciej Lewenstein. 1998-08-08. Dynamical Cooling of Trapped Gases I: One Atom Problem. https://doi.org/10.1103/physreva.59.613

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