Modulation instability in two component Bose-Einstein condensate with relative component motion

The development of modulation instability in a spatially homogeneous two-component Bose-Einstein condensate (BEC), in which the interacting components move through each other at a relative speed, is investigated. It is shown that nonlinear dynamics, leading to modulation instability, is determined by both the values of the constant interaction and the relative velocity between the components. The maximum oscillation increment is found and the limits of the existence of modulation instability in the space of wave numbers are determined. (author)