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arXiv · 0909.5090

Bose-Einstein condensation in dark power-law laser traps

Amine Jaouadi·Naceur Gaaloul·Bruno Viaris De Lesegno·Mourad Telmini·Laurence Pruvost·Eric Charron
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Abstract

We investigate theoretically an original route to achieve Bose-Einstein condensation using dark power-law laser traps. We propose to create such traps with two crossing blue-detuned Laguerre-Gaussian optical beams. Controlling their azimuthal order $\ell$ allows for the exploration of a multitude of power-law trapping situations in one, two and three dimensions, ranging from the usual harmonic trap to an almost square-well potential, in which a quasi-homogeneous Bose gas can be formed. The usual cigar-shaped and disk-shaped Bose-Einstein condensates obtained in a 1D or 2D harmonic trap take the generic form of a "finger" or of a "hockey puck" in such Laguerre-Gaussian traps. In addition, for a fixed atom number, higher transition temperatures are obtained in such configurations when compared with a harmonic trap of same volume. This effect, which results in a substantial acceleration of the condensation dynamics, requires a better but still reasonable focusing of the Laguerre-Gaussian beams.

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Amine Jaouadi, Naceur Gaaloul, Bruno Viaris De Lesegno, Mourad Telmini, Laurence Pruvost, Eric Charron. 2010-09-10. Bose-Einstein condensation in dark power-law laser traps. https://doi.org/10.1103/physreva.82.023613

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