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arXiv · physics/0401055

Narrow Line Cooling: Finite Photon Recoil Dynamics

Abstract

We present an extensive study of the unique thermal and mechanical dynamics for narrow-line cooling on the 1S0 - 3P1 88Sr transition. For negative detuning, trap dynamics reveal a transition from the semiclassical regime to the photon-recoil-dominated quantum regime, yielding an absolute minima in the equilibrium temperature below the single-photon recoil limit. For positive detuning, the cloud divides into discrete momentum packets whose alignment mimics lattice points on a face-centered-cubic crystal. This novel behavior arises from velocity selection and "positive feedback" acceleration due to a finite number of photon recoils. Cooling is achieved with blue-detuned light around a velocity where gravity balances the radiative force.

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Thomas H. Loftus, Tetsuya Ido, Andrew D. Ludlow, Martin M. Boyd, Jun Ye. 2004-07-10. Narrow Line Cooling: Finite Photon Recoil Dynamics. https://doi.org/10.1103/physrevlett.93.073003

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