Investigation of Spatiotemporal Optical Beam Reallocation

摘要

In the current work we study beam interaction in media with normal dispersion and self focusing nonlinearity, ruled by the two dimensional NLSE. The circular or elliptical Gaussian beams propagate over a continuous wave background (CW) which raises the X-like gain profile of Modulational Instability. That, along with self-focusing nonlinearity, can lead the beams to collision along the spatial dimension, then to fusion and finally to splitting and creation of two major filaments that move along the temporal dimension. Thus, the energy and momentum of the beams are effectively "reallocated" from one dimension to the other. By conducting primarily a numerical study, we reveal the relation of the resulting filaments to the interacting beams and the characteristics of the CW. Analytical description of this relation is also attempted and a new mechanism of beam-control is proposed. Explanation of the physical phenomena involved is also offered.