Interaction of nematicons in a bias-free liquid crystal cell

We study experimentally the propagation dynamics and interaction of spatial optical solitons in a bias-free cell filled with nematic liquid crystals. We reveal and measure long-range effects due to the cell boundaries for a single nematicon as well as for the interacting in-phase and out-of-phase nematicons. We discuss the effect of initial beam focusing and relative input angle on the interaction of in-phase nematicons. © 2009 Optical Society of America OCIS codes: (190.4400) Nonlinear optics, materials, (160.3710) Liquid crystals References and links 1. G. I. Stegeman and M. Segev, “Optical spatial solitons and their interactions: universality and diversity,” Science 286, 1518-1523 (1999). 2. Yu. S. Kivshar and G. P. Agrawal, Optical Solitons: From Fibers to Photonic Crystals (Academic Press, 2003). 3. N. V. Tabirian, A. V. Sukhov, B. Y. Zel’dovich, “Orientational optical nonlinearity of liquid crystals,” Mol. Cryst. Liq. Cryst. 136, 1-139 (1986). 4. I. C. 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