One-Dimensional Spatial Dark Soliton-Induced Channel Waveguides In Lithium Niobate Crystal

The anisotropic dependence of the formation of one-dimensional (1-D) spatial dark solitons on the orientation of intensity gradients in lithium niobate crystal is numerically specified. Based on this, we propose an approach to fabricate channel waveguides by employing 1-D spatial dark solitons. By exposure of two 1-D dark solitons with different orientations, channel waveguides can be created. The structures of the channel waveguides can be tuned by adjustment of the widths of the solitons and/or the angles between the two exposures. A square channel waveguide is experimentally demonstrated in an irondoped lithium niobate crystal by exposure of two orthogonal 1-D dark solitons in sequence. (c) 2006 Optical Society of America.