Journal of Low Temperature Physics

, Volume 171, Issue 3–4, pp 362–368 | Cite as

Pure Pairing Modes in Trapped Fermion Systems

  • P. Capuzzi
  • E. S. Hernández
  • L. Szybisz


We present numerical predictions for the shape of the pairing fluctuations in harmonically trapped atomic 6Li with two spin projections, based on the fluiddynamical description of cold fermions with pairing interactions. In previous works it has been shown that when the equilibrium of a symmetric mixture is perturbed, the linearized fluiddynamic equations decouple into two sets, one containing the sound mode of fermion superfluids and the other the pairing mode. The latter corresponds to oscillations of the modulus of the complex gap and is driven by the kinetic energy densities of the particles and of the pairs. Assuming proportionality between the heat flux and the energy gradient, the particle kinetic energy undergoes a diffusive behavior and the diffusion parameter is the key parameter for the relaxation time scale. We examine a possible range of values for this parameter and find that the shape of the pairing oscillation is rather insensitive to the precise value of the transport coefficient. Moreover, the pairing fluctuation is largely confined to the center of the trap, and the energy of the pairing mode is consistent with the magnitude of the equilibrium gap.


Fermion superfluid Harmonic confinement Pairing fluctuations Massive mode 



This work has been performed under grants PIP 0546 from CONICET, Argentina, and UBACYT 20020100200156 from University of Buenos Aires.


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  1. 1.Department of Physics, Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires, and Consejo Nacional de Investigaciones Científicas y TécnicasBuenos AiresArgentina
  2. 2.Comisión Nacional de Energía AtómicaBuenos AiresArgentina

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