Skew-self-adjoint Dirac systems with a rectangular matrix potential: Weyl theory, direct and inverse problems

A non-classical Weyl theory is developed for skew-self-adjoint Dirac systems with rectangular matrix potentials. The notion of the Weyl function is introduced and direct and inverse problems are solved. A Borg-Marchenko type uniqueness result and the evolution of the Weyl function for the corresponding focusing nonlinear Schr"odinger equation are also derived.