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Title: Single-particle excitations in a trapped gas of Fermi atoms in the BCS-BEC crossover region. II. Broad Feshbach resonance

Abstract

We apply the formulation developed in a recent paper [Y. Ohashi and A. Griffin, Phys. Rev. A 72, 013601 (2005)] for single-particle excitations in the BCS-BEC crossover to the case of a broad Feshbach resonance. At T=0, we solve the Bogoliubov-de Gennes coupled equations taking into account a Bose condensate of bound states (molecules). In the case of a broad resonance, the density profile n(r), as well as the profile of the superfluid order parameter {delta}-tilde(r), are spatially spread out to the Thomas-Fermi radius, even in the crossover region. This order parameter {delta}-tilde(r) suppresses the effects of low-energy Andreev bound states on the rf tunneling current. As a result, the peak energy in the rf spectrum is found to occur at an energy equal to the superfluid order parameter {delta}-tilde(r=0) at the center of the trap, in contrast to the case of a narrow resonance, and in agreement with recent measurements. The local density approximation is found to give a good approximation for the rf-tunneling spectrum.

Authors:
 [1];  [2]
  1. Institute of Physics, University of Tsukuba, Tsukuba, Ibaraki 305 (Japan)
  2. Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7 (Canada)
Publication Date:
OSTI Identifier:
20786343
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 72; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevA.72.063606; (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; APPROXIMATIONS; ATOMS; BCS THEORY; BOSE-EINSTEIN CONDENSATION; BOUND STATE; DENSITY; DENSITY FUNCTIONAL METHOD; ELECTRIC CURRENTS; EXCITATION; FERMIONS; MOLECULES; ORDER PARAMETERS; RESONANCE; SUPERFLUIDITY; THOMAS-FERMI MODEL; TRAPPING; TRAPS; TUNNEL EFFECT

Citation Formats

Ohashi, Y., and Griffin, A. Single-particle excitations in a trapped gas of Fermi atoms in the BCS-BEC crossover region. II. Broad Feshbach resonance. United States: N. p., 2005. Web. doi:10.1103/PHYSREVA.72.0.
Ohashi, Y., & Griffin, A. Single-particle excitations in a trapped gas of Fermi atoms in the BCS-BEC crossover region. II. Broad Feshbach resonance. United States. doi:10.1103/PHYSREVA.72.0.
Ohashi, Y., and Griffin, A. Thu . "Single-particle excitations in a trapped gas of Fermi atoms in the BCS-BEC crossover region. II. Broad Feshbach resonance". United States. doi:10.1103/PHYSREVA.72.0.
@article{osti_20786343,
title = {Single-particle excitations in a trapped gas of Fermi atoms in the BCS-BEC crossover region. II. Broad Feshbach resonance},
author = {Ohashi, Y. and Griffin, A.},
abstractNote = {We apply the formulation developed in a recent paper [Y. Ohashi and A. Griffin, Phys. Rev. A 72, 013601 (2005)] for single-particle excitations in the BCS-BEC crossover to the case of a broad Feshbach resonance. At T=0, we solve the Bogoliubov-de Gennes coupled equations taking into account a Bose condensate of bound states (molecules). In the case of a broad resonance, the density profile n(r), as well as the profile of the superfluid order parameter {delta}-tilde(r), are spatially spread out to the Thomas-Fermi radius, even in the crossover region. This order parameter {delta}-tilde(r) suppresses the effects of low-energy Andreev bound states on the rf tunneling current. As a result, the peak energy in the rf spectrum is found to occur at an energy equal to the superfluid order parameter {delta}-tilde(r=0) at the center of the trap, in contrast to the case of a narrow resonance, and in agreement with recent measurements. The local density approximation is found to give a good approximation for the rf-tunneling spectrum.},
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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