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arXiv · 0812.3088

Efficient formation of ground state ultracold molecules via STIRAP from the continuum at a Feshbach resonance

Elena Kuznetsova·Susanne F. Yelin·Marko Gacesa·Philippe Pellegrini·Robin Côté
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Abstract

We develop a complete theoretical description of photoassociative Stimulated Raman Adiabatic Passage (STIRAP) near a Feshbach resonance in a thermal atomic gas. We show that it is possible to use low intensity laser pulses to directly excite the continuum at a Feshbach resonance and transfer nearly the entire atomic population to the lowest rovibrational level in the molecular ground state. In case of a broad resonance, commonly found in several diatomic alkali molecules, our model predicts a transfer efficiency $η$ up to 97% for a given atom pair, and up to 70% when averaged over an atomic ensemble. The laser intensities and pulse durations needed for optimal transfer are $10^2-10^3$ W/cm$^2$ and several $μ$s. Such efficiency compares to or surpasses currently available techniques for creating stable diatomic molecules, and the versatility of this approach simplifies its potential use for many molecular species.

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Elena Kuznetsova, Susanne F. Yelin, Marko Gacesa, Philippe Pellegrini, Robin Côté. 2008-12-16. Efficient formation of ground state ultracold molecules via STIRAP from the continuum at a Feshbach resonance. https://doi.org/10.1088/1367-2630%2F11%2F5%2F055028

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