Collective excitations of a degenerate Fermi vapour in a magnetic trap

Citation
M. Amoruso et al., Collective excitations of a degenerate Fermi vapour in a magnetic trap, EUR PHY J D, 7(3), 1999, pp. 441-447
Citations number
25
Categorie Soggetti
Physics
Journal title
EUROPEAN PHYSICAL JOURNAL D
ISSN journal
14346060 → ACNP
Volume
7
Issue
3
Year of publication
1999
Pages
441 - 447
Database
ISI
SICI code
1434-6060(199910/11)7:3<441:CEOADF>2.0.ZU;2-1
Abstract
We evaluate the small-amplitude excitations of a spin-polarized vapour of F ermi atoms confined inside a harmonic trap. The dispersion law omega = omeg a f[l + 4n(n + l + 2)/3](1/2) is Obtained for the vapour in the collisional regime inside a spherical trap of frequency omega(f), with n the number of radial nodes and l the orbital angular momentum. The low-energy excitation s are also treated in the case of an axially symmetric harmonic confinement . The collisionless regime is discussed with main reference to a Landau-Bol tzmann equation for the Wigner distribution function: this equation is solv ed within a variational approach allowing an account of non-linearities. A comparative discussion of the eigenmodes of oscillation for confined Fermi and Bose vapours is presented in an Appendix.