Ultracold Atomic Interactions and Bose–Einstein Condensation

Atomic interactions play a crucial role in Bose-condensed alkali gases. The condensate self-energy, proportional to the two-body s-wave scattering length, strongly affects the stability and other properties of a condensate. Alkali atom scattering lengths have been determined only during the past few years by a combination of conventional molecular spectroscopy, photoassociation spectroscopy, and ultracold atomic collision studies. In this article, we present a brief review of alkali atom interactions and scattering length determinations.