Selfconsistent theory of atomic Fermi gases with a Feshbach resonance at the superfluid transition
Abstract
A selfconsistent theory is derived to describe the BCSBoseEinsteincondensate crossover for a strongly interacting Fermi gas with a Feshbach resonance. In the theory the fluctuation of the dressed molecules, consisting of both preformed Cooper pairs and 'bare' Feshbach molecules, has been included within a selfconsistent Tmatrix approximation, beyond the Nozieres and SchmittRink strategy considered by Ohashi and Griffin. The resulting selfconsistent equations are solved numerically to investigate the normalstate properties of the crossover at various resonance widths. It is found that the superfluid transition temperature T{sub c} increases monotonically at all widths as the effective interaction between atoms becomes more attractive. Furthermore, a residue factor Z{sub m} of the molecule's Green function and a complex effective mass have been determined to characterize the fraction and lifetime of Feshbach molecules at T{sub c}. Our manybody calculations of Z{sub m} agree qualitatively well with recent measurments of the gas of {sup 6}Li atoms near the broad resonance at 834 G. The crossover from narrow to broad resonances has also been studied.
 Authors:
 ARC Centre of Excellence for QuantumAtom Optics, Department of Physics, University of Queensland, Brisbane, Queensland 4072 (Australia)
 Publication Date:
 OSTI Identifier:
 20786350
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 72; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.72.063613; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; APPROXIMATIONS; ATOMS; BCS THEORY; BOSEEINSTEIN CONDENSATION; COOPER PAIRS; EFFECTIVE MASS; FERMI GAS; FERMIONS; FLUCTUATIONS; GREEN FUNCTION; LIFETIME; LITHIUM; LITHIUM 6; MANYBODY PROBLEM; MOLECULES; RESONANCE; S MATRIX; SUPERFLUIDITY; TRANSITION TEMPERATURE
Citation Formats
Liu Xiaji, and Hu Hui. Selfconsistent theory of atomic Fermi gases with a Feshbach resonance at the superfluid transition. United States: N. p., 2005.
Web. doi:10.1103/PHYSREVA.72.0.
Liu Xiaji, & Hu Hui. Selfconsistent theory of atomic Fermi gases with a Feshbach resonance at the superfluid transition. United States. doi:10.1103/PHYSREVA.72.0.
Liu Xiaji, and Hu Hui. Thu .
"Selfconsistent theory of atomic Fermi gases with a Feshbach resonance at the superfluid transition". United States.
doi:10.1103/PHYSREVA.72.0.
@article{osti_20786350,
title = {Selfconsistent theory of atomic Fermi gases with a Feshbach resonance at the superfluid transition},
author = {Liu Xiaji and Hu Hui},
abstractNote = {A selfconsistent theory is derived to describe the BCSBoseEinsteincondensate crossover for a strongly interacting Fermi gas with a Feshbach resonance. In the theory the fluctuation of the dressed molecules, consisting of both preformed Cooper pairs and 'bare' Feshbach molecules, has been included within a selfconsistent Tmatrix approximation, beyond the Nozieres and SchmittRink strategy considered by Ohashi and Griffin. The resulting selfconsistent equations are solved numerically to investigate the normalstate properties of the crossover at various resonance widths. It is found that the superfluid transition temperature T{sub c} increases monotonically at all widths as the effective interaction between atoms becomes more attractive. Furthermore, a residue factor Z{sub m} of the molecule's Green function and a complex effective mass have been determined to characterize the fraction and lifetime of Feshbach molecules at T{sub c}. Our manybody calculations of Z{sub m} agree qualitatively well with recent measurments of the gas of {sup 6}Li atoms near the broad resonance at 834 G. The crossover from narrow to broad resonances has also been studied.},
doi = {10.1103/PHYSREVA.72.0},
journal = {Physical Review. A},
number = 6,
volume = 72,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}

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