arXiv:cond-mat/0304546 · Physical Review Letters
Levinson-Like Theorem for Scattering from a Bose-Einstein Condensate
Joachim Brand, Ivo Häring, Jan Michael Rost
Abstract
A relation between the number of bound elementary excitations of an atomic Bose-Einstein condensate and the phase shift of elastically scattered atoms is derived. Within the Bogoliubov model of a weakly interacting Bose gas this relation is exact and generalizes Levinson's theorem. Specific features of the Bogoliubov model such as complex energy and continuum bound states are discussed and a numerical example is given.