An effective theory of Feshbach resonances and many-body properties of Fermi gases

Abstract

For calculating low-energy properties of a dilute gas of atoms interacting via a Feshbach resonance, we develop an effective theory in which the parameters that enter are an atom-molecule coupling strength and the magnetic moment of the molecular resonance. We demonstrate that for resonances in the fermionic systems ${}^6$Li and ${}^{40}$K that are under experimental investigation, the coupling is so strong that many-body effects are appreciable even when the resonance lies at an energy large compared with the Fermi energy. We calculate a number of many-body effects, including the effective mass and the lifetime of atomic quasiparticles in the gas.

4 pages, 1 figure, NORDITA-2003-21 CM

References in corpus (6)

• Observation of a Strongly-Interacting Degenerate Fermi Gas of Atoms
• Superfluid Fermi Gases with Large Scattering Length
• Decay of an ultracold fermionic lithium gas near a Feshbach resonance
• Superfluid transition temperature in a trapped gas of Fermi atoms with a Feshbach resonance
• The nature of Feshbach molecules in Bose-Einstein condensates
• Feshbach resonance in dense ultracold Fermi gases

Cited by in corpus (60)

• Many-Body Physics with Ultracold Gases
• Theory of ultracold Fermi gases
• Production of cold molecules via magnetically tunable Feshbach resonances
• Ultrafast many-body interferometry of impurities coupled to a Fermi sea
• The BCS-BEC crossover: From ultra-cold Fermi gases to nuclear systems
• Few-body physics with ultracold atomic and molecular systems in traps
• Impurity in a Bose-Einstein condensate and the Efimov effect
• Polaron to molecule transition in a strongly imbalanced Fermi gas
• Anisotropic Fermi Superfluid via p-wave Feshbach Resonance
• Viscous relaxation and collective oscillations in a trapped Fermi gas near the unitarity limit
• Shear viscosity and damping for a Fermi gas in the unitarity limit
• Pairing in a two-component ultracold Fermi gas: phases with broken space symmetries
• Diatomic molecules in ultracold Fermi gases - Novel composite bosons
• Viscosity and Thermal Relaxation for a resonantly interacting Fermi gas
• Stability of the fermionic gases close to a p-wave Feshbach resonance
• Universality of an impurity in a Bose-Einstein condensate
• Strongly-resonant p-wave superfluids
• Realization of a Resonant Fermi Gas with a Large Effective Range
• Atom-molecule coexistence and collective dynamics near a Feshbach resonance of cold fermions
• Decay of polarons and molecules in a strongly polarized Fermi gas
• Fate of the Bose polaron at finite temperature
• Conventional character of the BCS-BEC cross-over in ultra-cold gases of 40K
• Universality in Phase Transitions for Ultracold Fermionic Atoms
• Two-component Fermi gas with a resonant interaction
• Multi-channel scattering and Feshbach resonances: Effective theory, phenomenology, and many-body effects
• Polarons and dressed molecules near narrow Feshbach resonances
• Alternative Route to Strong Interaction: Narrow Feshbach Resonance
• Coherent molecular bound states of bosons and fermions near a Feshbach resonance
• Bragg Spectroscopy of Cold Atomic Fermi Gases
• Spin polarons and molecules in strongly-interacting atomic Fermi gases
• Pair tunneling, phase separation and dimensional crossover in imbalanced fermionic superfluids in a coupled array of tubes
• Atom-molecule theory of broad Feshbach resonances
• Population of closed-channel molecules in trapped Fermi gases with broad Feshbach resonances
• Scattering properties of weakly bound dimers of fermionic atoms
• Seeing Majorana fermions in time-of-flight images of spinless fermions coupled by s-wave pairing
• Detection of Chern numbers and entanglement in topological two-species systems through subsystem winding numbers
• Stability of fermionic Feshbach molecules in a Bose-Fermi mixture
• Pairing Symmetry in the Anisotropic Fermi Superfluid under p-wave Feshbach Resonance
• BCS-BEC Crossover in Atomic Fermi Gases with a Narrow Resonance
• Zero and First Sound in Normal Fermi Systems
• Feshbach molecule production in fermionic atomic gases
• Effective scattering and Efimov physics in the presence of two-body dissipation
• Superconductivity induced by strong electron-exciton coupling in doped atomically thin semiconductor heterostructures
• Fluctuations in the formation time of ultracold dimers from fermionic atoms
• Dressed-molecules in resonantly-interacting ultracold atomic Fermi gases
• Atom-molecule equilibration in a degenerate Fermi gas with resonant interactions
• Dynamic Structure Factor of Normal Fermi Gas from Collisionless to Hydrodynamic Regime
• Nonexponential decay of Feshbach molecules
• Feshbach Resonances and Medium Effects in ultracold atomic Gases
• Experimental realization of BCS-BEC crossover physics with a Fermi gas of atoms
• The three-body recombination of a condensed Bose gas near a Feshbach resonance
• Quasiparticle excitations in Bose-Fermi mixtures
• Momentum-dependent quasiparticle properties of the Fermi polaron from the functional renormalization group
• Periodic dynamics of fermionic superfluids in the BCS regime
• Non-universal Fermi polaron in quasi two-dimensional quantum gases
• Paired fermionic superfluids with s- and p-wave interactions
• Functional-renormalization-group approach to strongly coupled Bose-Fermi mixtures in two dimensions
• Phenomenological model of decaying Bose polarons
• Molecular regimes in ultracold Fermi gases
• Composite pairing and superfluidity in a one-dimensional resonant Bose-Fermi mixture