Translating oscillatory nonlinear structure in a plasma boundary

By means of a Madelung decomposition, exact periodic traveling solutions are constructed for a modified nonlinear Schrodinger equation derived by Stenflo and Gradov, describing electrostatic surface waves in semi-infinite plasma. The condition for the existence of bi-stable equilibria is discussed. A conservation law as well as the modulational instability admitted by the model are analyzed.
Comment: 8 figures