Self-Focussed and Self-Trapped Beams in Nonlinear Optics.

摘要

Self-focussing and self-trapping of light rays are studied in a classical two-dimensional nonlinear model both in the geometrical optics approximation and when retaining higher dispersion terms. The paraxial ray approximation of Akhmanov that leads to the nonlinear Schrodinger equation is specifically avoided. It is found that in the geometrical optics approximation, focussing must eventually occur once convergence of rays begins. When both diffraction and nonlinearity are present, however, focussing may or may not occur. (Author)