Universal quantum viscosity in a unitary Fermi gas.

Journal Article (Journal Article)

A Fermi gas of atoms with resonant interactions is predicted to obey universal hydrodynamics, in which the shear viscosity and other transport coefficients are universal functions of the density and temperature. At low temperatures, the viscosity has a universal quantum scale ħ n, where n is the density and ħ is Planck's constant h divided by 2π, whereas at high temperatures the natural scale is p(T)(3)/ħ(2), where p(T) is the thermal momentum. We used breathing mode damping to measure the shear viscosity at low temperature. At high temperature T, we used anisotropic expansion of the cloud to find the viscosity, which exhibits precise T(3/2) scaling. In both experiments, universal hydrodynamic equations including friction and heating were used to extract the viscosity. We estimate the ratio of the shear viscosity to the entropy density and compare it with that of a perfect fluid.

Full Text

Duke Authors

Cited Authors

  • Cao, C; Elliott, E; Joseph, J; Wu, H; Petricka, J; Schäfer, T; Thomas, JE

Published Date

  • January 2011

Published In

Volume / Issue

  • 331 / 6013

Start / End Page

  • 58 - 61

PubMed ID

  • 21148347

Electronic International Standard Serial Number (EISSN)

  • 1095-9203

International Standard Serial Number (ISSN)

  • 0036-8075

Digital Object Identifier (DOI)

  • 10.1126/science.1195219


  • eng