Superfuid-insulator transitions at non-integer filling in optical lattices of fermionic atoms

Abstract

We determine the superfluid transition temperatures $T_c$ and the ground states of the attractive Hubbard model and find new insulating phases associated with non-integer filling at sufficiently strong pairing attraction $|U|$. These states, distinct from band and Mott insulating phases, derive from pair localization; pair hopping at large $|U|$ and high densities is impeded by inter-site, inter-pair repulsive interactions. The best way to detect the breakdown of superfluidity is using fermionic optical lattices which should reveal new forms of ``bosonic'' order, reflecting ground state pairing without condensation.

4 pages, 3 figures, submitted to Phys. Rev. A

References in corpus (4)

• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• Evidence for Superfluidity of Ultracold Fermions in an Optical Lattice
• Critical Temperature and Thermodynamics of Attractive Fermions at Unitarity
• Superfluid-Insulator Transition of Strongly Interacting Fermi Gases in Optical Lattices

Cited by in corpus (15)

• Theory of Radio Frequency Spectroscopy Experiments in Ultracold Fermi Gases and Their Relation to Photoemission Experiments in the Cuprates
• Collective modes and superflow instabilities of strongly correlated Fermi superfluids
• Probing the BCS-BEC crossover with persistent currents
• Stability of Superflow for Ultracold Fermions in Optical Lattices
• Fermions with attractive interactions on optical lattices and implications for correlated systems
• Radio Frequency Spectroscopy of Trapped Fermi Gases with Population Imbalance
• Conserving T-matrix theory of superconductivity
• Multiband-Driven Superfluid-Insulator Transition of Fermionic Atoms in Optical Lattices: A Dynamical Mean-Field-Theory Study
• Spatially-modulated Superfluid States in Fermionic Optical Ladder Systems with Repulsive Interactions
• Unusual destruction and enhancement of superfluidity of atomic Fermi gases by population imbalance in a one-dimensional optical lattice
• Asymmetric Bethe-Salpeter equation for pairing and condensation
• Superfluidity and pairing phenomena in ultracold atomic Fermi gases in one-dimensional optical lattices, Part I: Balanced case
• Ground states of atomic Fermi gases in a two-dimensional optical lattice with and without population imbalance
• On the Boson-Fermion resonant model on a lattice
• Density-Wave and Antiferromagnetic States of Fermionic Atoms in Optical Lattices