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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Production of cold molecules in a magneto-optical trap

Laurentius Windholz

Published Apr 9, 2001• 0 citations
Publisher

Abstract

Production of translatory cold molecules from laser-cooled atomic ensembles is reviewed. Molecules in high vibrational levels of excited potentials are generated usually via photoassociation. For production of cold ground state molecules, up to now no general scheme is known.
DOI
10.1117/12.425137

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The methods producing cold molecules from cold atoms tend to leave molecular ensembles with substantial residual internal energy. For instance, cesium molecules initially formed via photoassociation of cold cesium atoms are in several vibrational levels nu of the electronic ground state. We applied a broadband femtosecond laser that redistributes the vibrational population in the ground state via a few electronic excitation/spontaneous emission cycles. The laser pulses are shaped to remove the excitation frequency band of the nu = 0 level, preventing re-excitation from that state. We observed a fast and efficient accumulation ( approximately 70% of the initially detected molecules) in the lowest vibrational level, nu = 0, of the singlet electronic state. The validity of this incoherent depopulation pumping method is very general and opens exciting prospects for laser cooling and manipulation of molecules.
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