39K Bose-Einstein condensate with tunable interactions.

G. Roati (1) , M. Zaccanti (1) , C. d'Errico (1) , Jacopo Catani (1) , Michele Modugno (1) , Andrea Simoni (2) , M. Inguscio (1) , Massimo Inguscio (1)

1 LENS - European Laboratory for Non-Linear Spectroscopy
2 PALMS - Physique des atomes, lasers, molécules et surfaces

We produce a Bose-Einstein condensate of 39K atoms. Condensation of this species with a naturally small and negative scattering length is achieved by a combination of sympathetic cooling with 87Rb and direct evaporation, exploiting the magnetic tuning of both inter- and intraspecies interactions at Feshbach resonances. We explore the tunability of the self-interactions by studying the expansion and the stability of the condensate. We find that a 39K condensate is interesting for future experiments requiring a weakly-interacting Bose gas.

Domaines: Biophysique

G. Roati, M. Zaccanti, C. d'Errico, Jacopo Catani, Michele Modugno, et al.. 39K Bose-Einstein condensate with tunable interactions.. Physical Review Letters, 2007, 99 (1), pp.010403. ⟨10.1103/PhysRevLett.99.010403⟩. ⟨hal-00908153⟩