We report optical switching studies on nematic liquid crystal incorporated into structures based on self-assembled colloids. We compare the electro-optic responses of liquid crystal imbibed into colloid-templated polymers, liquid crystal imbibed in the interstitial space of colloid crystals, and conventional polymer-dispersed liquid crystals. We characterize the Bragg diffraction of our templat...

Electric heating effects in the nematic liquid crystal change the liquid crystal physical properties and dynamics. We propose a model to quantitatively describe the heating effects caused by dielectric dispersion and ionic conductivity in the nematic liquid crystals upon the application of an ac electric field. The temperature increase of the liquid crystal cell is related to the properties of ...

Recent experiments have reported that ferroelectric nanoparticles have drastic effects on nematic liquid crystals-increasing the isotropic-nematic transition temperature by about 5 K, and greatly increasing the sensitivity to applied electric fields. To understand these effects, we develop a theory for the statistical mechanics of ferroelectric nanoparticles in liquid crystals. This theory pred...

Directed and true self-assembly mechanisms in nematic liquid crystal colloids rely on specific interactions between microparticles and the topological defects of the matrix. Most ordered structures formed in thin nematic cells are thus based on elastic multipoles consisting of a particle and nearby defects. Here, we report, for the first time to our knowledge, the existence of giant elastic dip...

2014 Surface torques exerted by a nematic liquid crystal on a solid plate are investigated. Three different geometries are considered. The torques are generated by applying a uniform magnetic field to the nematic sample and are measured by a torsion pendulum. The elastic constants of the nematic Liquid Crystal and the anchoring energy at the interface can be obtained by this kind of measurement...

We present a numerical method for solving two-dimensional nematic liquid crystal flows subject to a magnetic field. The dynamic equations of nematic liquid crystals are based on the Ericksen-Leslie dynamic theory. This theory accounts for fluid anisotropy and elastic stresses resulting from spatial distortion of the “director”, which is a vector field describing the local average molecular orie...

Texture formation in a binary mixture of a flexible polymer and a liquid crystal has been studied using a nonlocal kinetic model for phase separation in the presence of liquid crystalline order. The model takes into account couplings between phase separation, phase ordering, and texture formation. The phase separation-phase ordering coupling leads to orientation normal to local concentration gr...

The dynamic behavior of a nematic liquid crystal with added carbon nanotubes (CNTs) in an electric field was analyzed. A theoretical model based on elastic continuum theory was developed and the relaxation times of nematic liquid crystals with CNTs were evaluated. Experiments made with single-walled carbon nanotubes dispersed in nematic 4-cyano-4'-pentylbiphenyl (5CB) indicated a significant di...

Microparticles of arbitrary shapes immersed in the bulk of nematic fluids are known to produce dipolar or quadrupolar elastic distortions that can mediate long-range colloidal interactions. We use twophoton photopolymerization to obtain complex-shaped surface-bound microparticles that are then embedded into a nematic liquid crystal host with a uniform far-field director. By means of threedimens...

We report the determination of the Kerr constant (B) and the real part of the third-order nonlinear optic susceptibility (chi(3)) above the nematic-isotropic phase transition temperature (TNI) of a liquid crystal composed of bent-shaped molecules. The values of B and chi(3) just above (approximately 0.3 degrees C) TNI are approximately 8x10(-12) m/V2 and 5x10(-20) m2/V2, respectively. The estim...