Formation of a Bose condensate of stable molecules via a Feshbach resonance

We propose and analyze an approach to convert an atomic condensate into a condensate of diatomic molecules in the rovibrational ground state. The process consists of a stimulated Raman transition dramatically enhanced by a time-dependent magnetic field that sweeps over a field-induced Feshbach resonance. For a condensate of Na atoms a judicious choice of Feshbach resonance enhances the Raman transition probability by seven orders of magnitude. A conversion efficiency of 3% can be realized by a field varying over a resonance at B=853 G in the direction of increasing field strength. With the opposite direction an efficiency of 23% is realized