Photoassociation of sodium in a Bose-Einstein condensate

C. McKenzie, J. Hecker Denschlag, H. Haeffner, A. Browaeys, Luis E. E. de Araujo, F. K. Fatemi, K. M. Jones, J. E. Simsarian, D. Cho, A. Simoni, E. Tiesinga, P. S. Julienne, K. Helmerson, P. D. Lett, S. L. Rolston, W. D. Phillips

Published 2001-11-27, updated 2001-11-30Version 2

We report on the formation of ultra-cold Na$_2$ molecules using single-photon photoassociation of a Bose-Einstein condensate. The photoassociation rate, linewidth and light shift of the J=1, $v=135$ vibrational level of the \mterm{A}{1}{+}{u} molecular bound state have been measured. We find that the photoassociation rate constant increases linearly with intensity, even where it is predicted that many-body effects might limit the rate. Our observations are everywhere in good agreement with a two-body theory having no free parameters.