We report the results of a synchrotron x-ray reflectivity study of bulk liquid-crystal surfaces that are coated by thin wetting films of an immiscible liquid. The liquid-crystal subphase consisted of the nematic or isotropic phase of 4-octyl- 4;{'} -cyanobiphenyl (8CB), and the wetting film was formed by the fluorocarbon perfluoromethylcyclohexane (PFMC), a volatile liquid. The thickness of the...

Recent advances in our high-speed analog liquid crystal spatial light modulators (SLMs) will be presented. These advancements include higher pixel density, smaller pixel pitch, greatly improved optical efficiency, and higher speed operation. The new VLSI SLMs can utilize ferroelectric liquid crystal (FLC) or nematic liquid crystal (NLC) to achieve phase-only, amplitude-only and phase-amplitude-...

The observed anisotropy of the diamagnetic susceptibility, AX, for oriented nematic liquid crystals of poly-y-benzyl-L-glutamate (PBLG) in dichloromethane is 6.8 &0.7 x 10-9 emu/cm3. For a PBLG axial ratio of 150, a value of the twist elastic constant K22 = 582 x 10-8 dynes is calculated by measuring the critical magnetic field for untwisting the cholesteric supramolecular structure in the PBLG...

Recent advancements in our high-speed multi-level (analog) 512x512 liquid crystal Spatial Light Modulator (SLM) will be presented. These advancements include smaller pixel pitch, greatly improved optical efficiency, and higher speed operation. The new VLSI SLM can utilize Ferroelectric Liquid Crystal (FLC) or Nematic Liquid Crystal (NLC) to achieve phase-only, amplitude-only, and phase-amplitud...

A simple method for achieving high-contrast vertical alignment of high birefringence (Dn 0.28) negative dielectric anisotropic liquid crystal mixture using buffed polyimide substrates is demonstrated. By doping a positive, or non-polar dielectric anisotropic compound or mixture to the laterally difluorinated tolane liquid crystal host, an excellent vertical alignment was obtained. This alignmen...

We study the optical response of a metamaterial surface created by a lattice of split-ring resonators covered with a nematic liquid crystal and demonstrate millisecond timescale switching between electric and magnetic resonances of the metasurface. This is achieved due to a high sensitivity of liquid-crystal molecular reorientation to the symmetry of the metasurface as well as to the presence o...

We present a new method for the in-plane realignment of nematic liquid crystals in already fully assembled cells with uni-directionally rubbed polyimide as an aligning layer. We use nematic liquid crystals (NLCs) with a relatively high nematic-isotropic transition temperature and we focus the IR laser beam of the laser tweezers selectively onto one or the other of the inner interfaces. The heat...

A chiral nematic liquid crystal that is tilted by an angle θi with respect to a substrate is subjected to an ac electric field at frequency ω. The nematic director is found to oscillate azimuthally about the normal to the liquid crystal substrate interface at frequency ω, indicating that a nonzero polarization perpendicular to the molecular tilt plane exists at the interface. The interfacial po...

In this paper, numerical solutions to the equations for the Ericksen-Leslie dynamic theory are obtained for two-dimensional nematic liquid crystal flows subject to a magnetic field. A numerical method for solving the governing equations for 2D flows has been formulated. The governing equations are solved by a finite difference technique based on the GENSMAC methodology introduced by Tomé and Mc...

It has been predicted, but never confirmed, that colloidal particles in a nematic liquid crystal could be self-assembled by delocalized topological defects and entangled disclinations. We show experimentally and theoretically that colloidal dimers and 1D structures bound by entangled topological defect loops can indeed be created by locally thermally quenching a thin layer of the nematic liquid...