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arXiv:cond-mat/0607667 · Physical Review Letters

Observation of Heteronuclear Feshbach Molecules from a Rb85–Rb87 Gas

Scott B. Papp, Carl Wieman

Published Oct 31, 2006• 163 citations
arXivHTMLPDF

Abstract

We report on the observation of ultracold heteronuclear Feshbach molecules. Starting with a $^{87}\mathrm{Rb}$ Bose-Einstein condensate and a cold atomic gas of $^{85}\mathrm{Rb}$, we utilize previously unobserved interspecies Feshbach resonances to create up to 25 000 molecules. Even though the $^{85}\mathrm{Rb}$ gas is nondegenerate, we observe a large molecular conversion efficiency due to the presence of a quantum degenerate $^{87}\mathrm{Rb}$ gas; this represents a key feature of our system. We compare the molecule creation at two different Feshbach resonances with different magnetic-field widths. The two Feshbach resonances are located at $265.44\ifmmode\pm\else\textpm\fi{}0.15\text{ }\mathrm{G}$ and $372.4\ifmmode\pm\else\textpm\fi{}1.3\text{ }\text{ }\mathrm{G}$. We also directly measure the small binding energy of the molecules through resonant magnetic-field association.

DOI
10.1103/physrevlett.97.180404

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