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Title: Trapped resonant fermions above the superfluid transition temperature

Abstract

We investigate trapped resonant fermions with unequal populations within the local density approximation above the superfluid transition temperature. By tuning the attractive interaction between fermions via Feshbach resonance, the system evolves from weakly interacting fermi gas to strongly interacting fermi gas, and finally becomes a Bose-Fermi mixture. The density profiles of fermions are examined and compared with experiments. We also point out the simple relationships between the local density, the axial density, and the gas pressure within the local density approximation.

Authors:
;  [1]
  1. Institute of Physics, Academia Sinica, Taipei 115, Taiwan (China)
Publication Date:
OSTI Identifier:
20976643
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevB.75.014526; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; APPROXIMATIONS; BOSONS; DENSITY; DENSITY FUNCTIONAL METHOD; FERMI GAS; FERMIONS; MIXTURES; SUPERFLUIDITY; TRANSITION TEMPERATURE; TRAPPING

Citation Formats

Cheng, C.-H., and Yip, S.-K. Trapped resonant fermions above the superfluid transition temperature. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.014526.
Cheng, C.-H., & Yip, S.-K. Trapped resonant fermions above the superfluid transition temperature. United States. doi:10.1103/PHYSREVB.75.014526.
Cheng, C.-H., and Yip, S.-K. Mon . "Trapped resonant fermions above the superfluid transition temperature". United States. doi:10.1103/PHYSREVB.75.014526.
@article{osti_20976643,
title = {Trapped resonant fermions above the superfluid transition temperature},
author = {Cheng, C.-H. and Yip, S.-K.},
abstractNote = {We investigate trapped resonant fermions with unequal populations within the local density approximation above the superfluid transition temperature. By tuning the attractive interaction between fermions via Feshbach resonance, the system evolves from weakly interacting fermi gas to strongly interacting fermi gas, and finally becomes a Bose-Fermi mixture. The density profiles of fermions are examined and compared with experiments. We also point out the simple relationships between the local density, the axial density, and the gas pressure within the local density approximation.},
doi = {10.1103/PHYSREVB.75.014526},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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  • We discuss the collective modes of a trapped Bose gas in the hydrodynamic regime where atomic collisions ensure local thermal equilibrium for the distribution function. Starting from the conservation laws, in the linearized limit we derive a closed equation for the velocity fluctuations in a trapped Bose gas above the Bose-Einstein transition temperature. Explicit solutions for a parabolic trap are given. We find that the surface modes above the transition have the same dispersion relation as the one recently obtained by Stringari for the oscillations of the condensate at T=0 within the Thomas-Fermi approximation. Results are also given for themore » monopole {open_quotes}breathing{close_quote}{close_quote} mode as well as for the m=0 excitations which result from the coupling of the monopole and quadrupole modes in an anisotropic parabolic well. {copyright} {ital 1997} {ital The American Physical Society}« less