NAGAYA , Tomoyuki

We study the zigzag instability coarsening of splay-bend walls formed in a nematic liquid crystal under external fields. The vertexes of zigzag can be considered as kinks in a one-dimensional order parameter system and the geometrical constraints associated with the necessary equal length sum of zig and zag segments impose a conserved quantity...

ILCC2002 Conference Proceedings

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When bistability and diffraction are simultaneously present, a Liquid-Crystal-Light-Valve with optical feedback shows the appearance of localised structures. We report here new features of their dynamics, such as their appearance on successive and concentric rings and their motion along the rings. Radial and azimuthal dynamics are presented and...

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In this article we review the conditions for the appearance of localized states in a nonlinear optical system, with particular reference to the liquid crystal light valve (LCLV) experiment. The localized structures here described are of dissipative type; that is, they represent the localized solutions of a pattern-forming system. We discuss...

The dynamics of the petal-like patterns observed in a liquid crystal light valve with optical feedback are investigated both experimentally and numerically. Based on a phenomenological model, the linear stability analysis predicts the bistability of the liquid crystal tilt angle for several voltage ranges that agrees with the experimental...

We show that in a liquid-crystal-light-valve with optical feedback the Fréedericksz transition displays a subcritical character. Experimentally, we determine the extension of the bistable region and we study the propagation of fronts connecting the different metastable states. Theoretically, we derive an amplitude equation, valid close to the...

réedericksz transition can become subcritical in the presence of a feedback mechanism that leads to the dependence of the local electric field onto the liquid crystal re-orientation angle. We have characterized experimentally the first-order Fréedericksz transition in a Liquid Crystal Light Valve with optical feedback. The bistability region is...

Stochastic resonance is a noise phenomenon that benefits applications such as pattern formation, neural systems, microelectromechanical systems, and image processing. This study experimentally clarifies that the orientation of the liquid crystal molecules was switched between two stable positions when stochastic resonance was induced by colored...