Energy measurement and virial theorem for confined universal Fermi gases

Journal Article (Journal Article)

Optically trapped two-component Fermi gases near a broad Feshbach resonance exhibit universal thermodynamics, where the properties of the gas are independent of the details of the two-body scattering interactions. We show that the measured cloud profiles of both species determine the total energy of universal gases for any trapping potential U and any spin mixture, without assuming either the local density approximation or harmonic confinement. A global proof of the virial theorem yields the total energy of the gas at all temperatures in the scale-invariant form E= ?U/ , where ? is an arbitrary energy scale in terms of which all length and energy scales that appear in the confining potential are written. This result enables model-independent energy measurement in any trap by observing only the cloud profiles, and provides a consistency check for many-body calculations in the universal regime. © 2008 The American Physical Society.

Full Text

Duke Authors

Cited Authors

  • Thomas, JE

Published Date

  • July 23, 2008

Published In

Volume / Issue

  • 78 / 1

Electronic International Standard Serial Number (EISSN)

  • 1094-1622

International Standard Serial Number (ISSN)

  • 1050-2947

Digital Object Identifier (DOI)

  • 10.1103/PhysRevA.78.013630

Citation Source

  • Scopus