Creation of "dark-soliton" atoms

Abstract

Dark solitons are thought to always repel so that bound states of dark solitons do not form. We show that quantum fluctuations of the background induce attractive forces between dark optical solitons. We clarify the nature of these fluctuations. Together with the repulsive potential, this attractive force creates a potential similar to that in a diatomic molecule which allows for the formation of bound pairs of dark solitons. Such pairs can be useful in the creation of notch arrays and crystal-like structures. © 2011 Europhysics Letters Association.