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arXiv · 1011.4372

Runaway evaporation for optically dressed atoms

David Wilkowski
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Abstract

Forced evaporative cooling in a far-off-resonance optical dipole trap is proved to be an efficient method to produce fermionic- or bosonic-degenerated gases. However in most of the experiences, the reduction of the potential height occurs with a diminution of the collision elastic rate. Taking advantage of a long-living excited state, like in two-electron atoms, I propose a new scheme, based on an optical knife, where the forced evaporation can be driven independently of the trap confinement. In this context, the runaway regime might be achieved leading to a substantial improvement of the cooling efficiency. The comparison with the different methods for forced evaporation is discussed in the presence or not of three-body recombination losses.

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David Wilkowski. 2010-11-19. Runaway evaporation for optically dressed atoms. https://doi.org/10.1088/0953-4075/43/20/205306

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