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Title: Acoustic Attenuation Probe for Fermion Superfluidity in Ultracold-Atom Gases

Abstract

Dilute gas Bose-Einstein condensates (BEC's), currently used to cool fermionic atoms in atom traps, can also probe the superfluidity of these fermions. The damping rate of BEC-acoustic excitations (phonon modes), measured in the middle of the trap as a function of the phonon momentum, yields an unambiguous signature of BCS-like superfluidity, provides a measurement of the superfluid gap parameter, and gives an estimate of the size of the Cooper pairs in the BEC-BCS crossover regime. We also predict kinks in the momentum dependence of the damping rate which can reveal detailed information about the fermion quasiparticle dispersion relation.

Authors:
 [1];  [2]; ; ;  [3];  [1]
  1. Department of Physics, Boston College, Chestnut Hill, Massachusetts 02167 (United States)
  2. (United States)
  3. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
Publication Date:
OSTI Identifier:
20957739
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevLett.98.110407; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMS; ATTENUATION; BOSE-EINSTEIN CONDENSATION; COOPER PAIRS; DAMPING; DISPERSION RELATIONS; EXCITATION; FERMIONS; GASES; PHONONS; SUPERFLUIDITY; TRAPS

Citation Formats

Gaudio, Sergio, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Mihaila, Bogdan, Blagoev, Krastan B., Timmermans, Eddy, and Bedell, Kevin S.. Acoustic Attenuation Probe for Fermion Superfluidity in Ultracold-Atom Gases. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.110407.
Gaudio, Sergio, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Mihaila, Bogdan, Blagoev, Krastan B., Timmermans, Eddy, & Bedell, Kevin S.. Acoustic Attenuation Probe for Fermion Superfluidity in Ultracold-Atom Gases. United States. doi:10.1103/PHYSREVLETT.98.110407.
Gaudio, Sergio, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, Mihaila, Bogdan, Blagoev, Krastan B., Timmermans, Eddy, and Bedell, Kevin S.. Fri . "Acoustic Attenuation Probe for Fermion Superfluidity in Ultracold-Atom Gases". United States. doi:10.1103/PHYSREVLETT.98.110407.
@article{osti_20957739,
title = {Acoustic Attenuation Probe for Fermion Superfluidity in Ultracold-Atom Gases},
author = {Gaudio, Sergio and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 and Mihaila, Bogdan and Blagoev, Krastan B. and Timmermans, Eddy and Bedell, Kevin S.},
abstractNote = {Dilute gas Bose-Einstein condensates (BEC's), currently used to cool fermionic atoms in atom traps, can also probe the superfluidity of these fermions. The damping rate of BEC-acoustic excitations (phonon modes), measured in the middle of the trap as a function of the phonon momentum, yields an unambiguous signature of BCS-like superfluidity, provides a measurement of the superfluid gap parameter, and gives an estimate of the size of the Cooper pairs in the BEC-BCS crossover regime. We also predict kinks in the momentum dependence of the damping rate which can reveal detailed information about the fermion quasiparticle dispersion relation.},
doi = {10.1103/PHYSREVLETT.98.110407},
journal = {Physical Review Letters},
number = 11,
volume = 98,
place = {United States},
year = {Fri Mar 16 00:00:00 EDT 2007},
month = {Fri Mar 16 00:00:00 EDT 2007}
}
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