Steady state solutions for nonlinear Schrödinger equation arising in optics.

In this paper, we use the method of calculus of variations to develop an existence theory for the steady state solutions of a nonlinear Schrödinger equation modeling light waves propagating in a photorefractive crystal. We show via direct minimization and mountain-pass argument that there exist steady state solutions realizing a continuous spectrum of energy points or wavenumbers. [ABSTRACT FROM AUTHOR]