Excitations at the border of a condensate
arXiv:1504.03164 · doi:10.1088/0953-4075/48/16/165302
Abstract
We solve the Bogoliubov--de Gennes equations for an inhomogeneous condensate in the vicinity of a linear turning point. A stable integration scheme is developed using a transformation into an adiabatic basis. We identify boundary modes trapped in a potential whose shape is similar to a Hartree-Fock mean-field treatment. These modes are non-resonantly excited when bulk modes reflect at the turning point and contribute significantly to the spectrum of local density fluctuations.