Sound propagation and quantum limited damping in a two-dimensional Fermi gas - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Physical Review Letters Année : 2020

Sound propagation and quantum limited damping in a two-dimensional Fermi gas

Lennart Sobirey
  • Fonction : Auteur
Niclas Luick
  • Fonction : Auteur
Hauke Biss
  • Fonction : Auteur
Tilman Enss
  • Fonction : Auteur
Thomas Lompe
  • Fonction : Auteur
Henning Moritz
  • Fonction : Auteur

Résumé

Strongly interacting two-dimensional Fermi systems are one of the great remaining challenges in many-body physics due to the interplay of strong local correlations and enhanced long-range fluctuations. Here, we probe the thermodynamic and transport properties of a 2D Fermi gas across the BEC-BCS crossover by studying the propagation and damping of sound modes. We excite particle currents by imprinting a phase step onto homogeneous Fermi gases trapped in a box potential and extract the speed of sound from the frequency of the resulting density oscillations. We measure the speed of sound across the BEC-BCS crossover and compare the resulting dynamic measurement of the equation of state both to a static measurement based on recording density profiles and to quantum Monte Carlo calculations and find reasonable agreement between all three. We also measure the damping of the sound mode, which is determined by the shear and bulk viscosities as well as the thermal conductivity of the gas. We find that the damping is minimal in the strongly interacting regime and the diffusivity approaches the universal quantum bound ℏ/m of a perfect fluid.

Dates et versions

hal-02518036 , version 1 (24-03-2020)

Identifiants

Citer

Markus Bohlen, Lennart Sobirey, Niclas Luick, Hauke Biss, Tilman Enss, et al.. Sound propagation and quantum limited damping in a two-dimensional Fermi gas. Physical Review Letters, 2020, 124 (24), pp.240403. ⟨10.1103/PhysRevLett.124.240403⟩. ⟨hal-02518036⟩
56 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More