Tuning of Heteronuclear Interactions in a Degenerate Fermi-Bose Mixture

Journal Article · Fri Sep 22 04:00:00 EDT 2006 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.97.120403· OSTI ID:20860839

Ospelkaus, S; Ospelkaus, C; Humbert, L; Sengstock, K; Bongs, K ^[1]

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1. Institut fuer Laserphysik, Luruper Chaussee 149, 22761 Hamburg (Germany)

We demonstrate tuning of interactions between fermionic {sup 40}K and bosonic {sup 87}Rb atoms by Feshbach resonances and access the complete phase diagram of the harmonically trapped mixture from phase separation to collapse. On the attractive side of the resonance, we observe a strongly enhanced mean-field energy of the condensate due to the mutual mean-field confinement, predicted by a Thomas-Fermi model. As we increase heteronuclear interactions beyond a threshold, we observe an induced collapse of the mixture. On the repulsive side of the resonance, we observe vertical phase separation of the mixture in the presence of the gravitational force, thus entering a completely unexplored part of the phase diagram of the mixture. In addition, we identify the 515 G resonance as p wave by its characteristic doublet structure.

• OSTI ID: 20860839
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 12 Vol. 97; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BOSE-EINSTEIN GAS
CONFINEMENT
FERMI GAS
MEAN-FIELD THEORY
MIXTURES
P WAVES
PHASE DIAGRAMS
POTASSIUM 40
RESONANCE
RUBIDIUM 87
THOMAS-FERMI MODEL