Role of Particle Interactions in the Feshbach Conversion of Fermion Atoms to Bosonic Molecules

Abstract

We investigate the Feshbach conversion of fermion atomic pairs to condensed boson molecules with a microscopic model that accounts the repulsive interactions among all the particles involved. We find that the conversion efficiency is enhanced by the interaction between boson molecules while suppressed by the interactions between fermion atoms and between atom and molecule. In certain cases, the combined effect of these interactions leads to a ceiling of less than 100% on the conversion efficiency even in the adiabatic limit. Our model predicts a non-monotonic dependence of the efficiency on mean atomic density. Our theory agrees well with recent experiments on ${}^6$Li and ${}^{40}$K.

5 pages, 4 figures

References in corpus (9)

• Crossover from a molecular Bose-Einstein condensate to a degenerate Fermi gas
• Weakly bound dimers of fermionic atoms
• Adiabatic Theory of Nonlinear Evolution of Quantum States
• Nonequilibrium dynamics and thermodynamics of a degenerate Fermi gas across a Feshbach resonance
• Adiabatic association of ultracold molecules via magnetic field tunable interactions
• Many-body effects on adiabatic passage through Feshbach resonances
• Molecular production in two-component atomic Fermi gases
• BCS-BEC crossover and quantum phase transition for 6Li and 40K atoms across Feshbach resonance
• Conversion Efficiencies of Heteronuclear Feshbach Molecules

Cited by in corpus (5)

• Many-body adiabatic passage: Quantum detours around chaos
• Parametric tuning of quantum phase transitions in ultracold reactions
• Cyclotron dynamics of a Bose-Einstein condensate in a quadruple-well potential with synthetic gauge fields
• Interaction-induced instability and chaos in the photoassociative stimulated Raman adiabatic passage from atomic to molecular Bose-Einstein condensates
• Observation of collectivity enhanced magnetoassociation of ${}^6$Li in the quantum degenerate regime