Dark photorefractive photovoltaic spatial solitons are demonstrated at 532 nm in nominally undoped and slightly Fe-doped LiNbO<sub>3</sub> planar optical waveguides. The spatial solitons are observed in a transient regime before transverse modulation instability occurs. Their widths are intensity independent as predicted by theory. Meanwhile, excited mode distribution and Fe-doping concentration are shown to influence soliton width. The guiding properties of soliton-induced waveguides are also presented.
© 2001 Optical Society of America
M. Chauvet, S. Chauvin, and H. Maillotte, "Transient dark photovoltaic spatial solitons and induced guiding in slab LiNbO3 waveguides," Opt. Lett. 26, 1344-1346 (2001)