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Title: Measurement of Sound Velocity in a Fermi Gas near a Feshbach Resonance

Abstract

Sound waves are excited in an optically trapped degenerate Fermi gas of spin-up and spin-down atoms with magnetically tunable interactions. Measurements are made throughout the crossover region, from a weakly interacting Fermi gas through the resonant Fermi superfluid regime to a Bose condensate of dimer molecules. The measured sound velocities test theories of hydrodynamic wave propagation and predictions of the equation of state. At resonance, the sound velocity exhibits universal scaling with the Fermi velocity, to within 1.8% over a factor of 30 in density.

Authors:
; ; ; ; ;  [1]
  1. Department of Physics, Duke University, Durham, North Carolina, 27708 (United States)
Publication Date:
OSTI Identifier:
20951263
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 17; Other Information: DOI: 10.1103/PhysRevLett.98.170401; (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; BOSE-EINSTEIN CONDENSATION; EQUATIONS OF STATE; FERMI GAS; RESONANCE; SOUND WAVES; SPIN; SUPERFLUIDITY; VELOCITY; WAVE PROPAGATION

Citation Formats

Joseph, J., Clancy, B., Luo, L., Kinast, J., Turlapov, A., and Thomas, J. E. Measurement of Sound Velocity in a Fermi Gas near a Feshbach Resonance. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.170401.
Joseph, J., Clancy, B., Luo, L., Kinast, J., Turlapov, A., & Thomas, J. E. Measurement of Sound Velocity in a Fermi Gas near a Feshbach Resonance. United States. doi:10.1103/PHYSREVLETT.98.170401.
Joseph, J., Clancy, B., Luo, L., Kinast, J., Turlapov, A., and Thomas, J. E. Fri . "Measurement of Sound Velocity in a Fermi Gas near a Feshbach Resonance". United States. doi:10.1103/PHYSREVLETT.98.170401.
@article{osti_20951263,
title = {Measurement of Sound Velocity in a Fermi Gas near a Feshbach Resonance},
author = {Joseph, J. and Clancy, B. and Luo, L. and Kinast, J. and Turlapov, A. and Thomas, J. E.},
abstractNote = {Sound waves are excited in an optically trapped degenerate Fermi gas of spin-up and spin-down atoms with magnetically tunable interactions. Measurements are made throughout the crossover region, from a weakly interacting Fermi gas through the resonant Fermi superfluid regime to a Bose condensate of dimer molecules. The measured sound velocities test theories of hydrodynamic wave propagation and predictions of the equation of state. At resonance, the sound velocity exhibits universal scaling with the Fermi velocity, to within 1.8% over a factor of 30 in density.},
doi = {10.1103/PHYSREVLETT.98.170401},
journal = {Physical Review Letters},
number = 17,
volume = 98,
place = {United States},
year = {Fri Apr 27 00:00:00 EDT 2007},
month = {Fri Apr 27 00:00:00 EDT 2007}
}
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