Collective mode damping and viscosity in a 1D unitary Fermi gas

Abstract

We calculate the damping of the Bogoliubov-Anderson mode in a one-dimensional two-component attractive Fermi gas for arbitrary coupling strength within a quantum hydrodynamic approach. Using the Bethe-Ansatz solution of the 1D BCS-BEC crossover problem, we derive analytic results for the viscosity covering the full range from a Luther-Emery liquid of weakly bound pairs to a Lieb-Liniger gas of strongly bound bosonic dimers. At the unitarity point, the system is a Tonks-Girardeau gas with a universal constant ${\alpha }_{\zeta }=0.38$ in the viscosity $\zeta ={\alpha }_{\zeta }\hslash n$ for T=0. For the trapped case, we calculate the Q-factor of the breathing mode and show that the damping provides a sensitive measure of temperature in 1D Fermi gases.

9 pages, 3 figures, published version (minor changes)

References in corpus (9)

• Viscosity in Strongly Interacting Quantum Field Theories from Black Hole Physics
• Vortices and Superfluidity in a Strongly Interacting Fermi Gas
• Observation of the Pairing Gap in a Strongly Interacting Fermi Gas
• Weakly bound dimers of fermionic atoms
• Collective excitations of a degenerate gas at the BEC-BCS crossover
• General coordinate invariance and conformal invariance in nonrelativistic physics: Unitary Fermi gas
• Exact coherent states of a harmonically confined Tonks-Girardeau gas
• An exactly solvable model of the BCS-BEC crossover
• Four-body problem and BEC-BCS crossover in a quasi-one-dimensional cold fermion gas

Cited by in corpus (3)

• Many-Body Physics with Ultracold Gases
• Viscosity and scale invariance in the unitary Fermi gas
• Viscous Flow in a 1D Spin-Polarized Fermi Gas: the Role of Integrability on Viscosity