Self-Trapping of Bosons and Fermions in Optical Lattices

Abstract

We theoretically investigate the enhanced localization of bosonic atoms by fermionic atoms in three-dimensional optical lattices and find a self-trapping of the bosons for attractive boson-fermion interaction. Because of this mutual interaction, the fermion orbitals are substantially squeezed, which results in a strong deformation of the effective potential for bosons. This effect is enhanced by an increasing bosonic filling factor leading to a large shift of the transition between the superfluid and the Mott-insulator phase. We find a nonlinear dependency of the critical potential depth on the boson-fermion interaction strength. The results, in general, demonstrate the important role of higher Bloch bands for the physics of attractively interacting quantum gas mixtures in optical lattices and are of direct relevance to recent experiments with 87Rb - 40K mixtures, where a large shift of the critical point has been found.

4 pages, 4 figures. Published version

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Cited by in corpus (20)

• Non-standard Hubbard models in optical lattices: a review
• Emergence of coherence and the dynamics of quantum phase transitions
• Role of interactions in 87Rb-40K Bose-Fermi mixtures in a 3d optical lattice
• Coherent Interaction of a Single Fermion with a Small Bosonic Field
• Observation of Density-Induced Tunneling
• Bose-Hubbard model with occupation dependent parameters
• Generalized Dynamical Mean-Field Theory for Bose-Fermi Mixtures in Optical Lattices
• Effect of interactions on harmonically confined Bose-Fermi mixtures in optical lattices
• Optimal time-dependent lattice models for nonequilibrium dynamics
• Loss of superfluidity by fermions in the boson Hubbard model on an optical lattice
• Self-localization of a small number of Bose particles in a superfluid Fermi system
• Effects of a dilute gas of fermions on the superfluid-insulator phase diagram of the Bose-Hubbard model
• Boson Hubbard model with weakly coupled Fermions
• Heteronuclear quantum gas mixtures
• Bose-Fermi solid and its quantum melting in an one-dimensional optical lattice
• Spin-selective insulators in Bose-Fermi mixtures
• Bose-Hubbard model with random impurities: Multiband and nonlinear hopping effects
• Staggered quantum phases of dipolar bosons at finite temperatures
• Insulator phases of Bose-Fermi mixtures induced by intraspecies next-neighbor interactions
• Isospin Correlations in two-partite Hexagonal Optical Lattices