Vector rogue waves in the mixed coupled nonlinear Schrodinger equations

In this paper, via the generalized Darboux transformation we derive the reduced and non-reduced vector rogue wave solutions of the focusing-defocusing mixed coupled nonlinear Schrodinger equations. The dynamics of reduced vector rogue waves is the same as that for the known scalar ones. The non-reduced solutions can exhibit both the one-peak-two-valleys structure with one peak and two valleys lying in a straight line, and the two-peaks-two-valleys structure with two peaks and two valleys located at the four vertices of a parallelogram. We also find that the amplitude of the non-reduced vector rogue wave is not three times as that of the exciting plane wave, and that the coalescence of multiple fundamental rogue waves does not generate larger-amplitude rogue waves. In addition, we discuss the relationship of the free parameters in the solutions with the positions and relative distances of rogue waves in the xt-plane.