Barrier transmission for the nonlinear Schroedinger equation: surprises of nonlinear transport

In this paper we report on a peculiar property of barrier transmission that systems governed by the nonlinear Schroedinger equation share with the linear one: for unit transmission the potential can be divided at an arbitrary point into two sub-potentials, a left and a right one, which have exactly the same transmission. This is a rare case of an exact property of a nonlinear wavefunction which will be of interest, e.g., for studies of coherent transport of Bose-Einstein condensates through mesoscopic waveguides