English

Collective modes of a two-dimensional spin-1/2 Fermi gas in a harmonic trap

Quantum Gases 2013-05-30 v2 Strongly Correlated Electrons

Abstract

We derive analytical expressions for the frequency and damping of the lowest collective modes of a two-dimensional Fermi gas using kinetic theory. For strong coupling, we furthermore show that pairing correlations overcompensate the effects of Pauli blocking on the collision rate for a large range of temperatures, resulting in a rate which is larger than that of a classical gas. Our results agree well with experimental data, and they recover the observed cross-over from collisionless to hydrodynamic behaviour with increasing coupling for the quadruple mode. Finally, we show that a trap anisotropy within the experimental bounds results in a damping of the breathing mode which is comparable to what is observed, even for a scale invariant system.

Keywords

Cite

@article{arxiv.1301.0358,
  title  = {Collective modes of a two-dimensional spin-1/2 Fermi gas in a harmonic trap},
  author = {Stefan K. Baur and Enrico Vogt and Michael Köhl and Georg M. Bruun},
  journal= {arXiv preprint arXiv:1301.0358},
  year   = {2013}
}

Comments

8 pages, 3 figures (published version)