Isospin excitations of a trapped 1D gas of attractively interacting fermions
arXiv:0712.4081
Abstract
We consider a gas of fermions with a short-range attractive intercomponent interaction in a parabolic external potential and derive the conditions of the local density approximation. The obtained spectrum of quasiparticle (isospin) excitations shows equidistant low-energy levels, which is equivalent to a linear momentum dependence and is fundamentally different from the ordinary Dirac spectrum in the spatially uniform case.
arXiv comment4 pages, 1 figure; minor corrections