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A Twist‐Bend Nematic Phase Driven by Hydrogen Bonding
Angewandte Chemie International Edition, 2014AbstractThe liquid crystalline phase behavior of 4‐[6‐(4′‐cyanobiphenyl‐4‐yl)hexyloxy]benzoic acid (CB6OBA) and 4‐[5‐(4′‐cyanobiphenyl‐4‐yloxy)pentyloxy]benzoic acid (CBO5OBA) is described. Both acids show an enantiotropic nematic phase attributed to the formation of supramolecular complexes by hydrogen bonding between the benzoic acid units.
Jansze, S.M. +4 more
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The two-phase twisted-ring counter circuit
2002 IEEE International Symposium on Circuits and Systems. Proceedings (Cat. No.02CH37353), 2003The behavior of the two-phase twisted-ring counter (2P-TRC) circuit is analyzed. The circuit produces two individual phased clock signals that exercise a phase difference equal to the half period of the clock. A tree-like structure is built by applying the phased outputs of the circuit to the clock inputs of two replicas of the circuit in order to ...
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Twist phase in Gaussian-beam optics
Journal of the Optical Society of America A, 1998The recently discovered twist phase is studied in the context of the full ten-parameter family of partially coherent general anisotropic Gaussian Schell-model beams. It is shown that the nonnegativity requirement on the cross-spectral density of the beam demands that the strength of the twist phase be bounded from above by the inverse of the transverse
Simon, R, Mukunda, N
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Liquid crystal phase shifters with a twist
Applied Physics Letters, 2013The phase-shift per unit-length of microwave radiation passing through a liquid crystal cell is calculated. By using twisted nematics, as compared to the standard homogeneous nematic liquid crystal, the phase-shift per unit-length is increased over the transition region.
C. M. Karwin, K. L. Livesey
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On the Twisted Director Field of the Blue Phases
Europhysics Letters (EPL), 1993We study the properties of special double-twist fields with toroidal symmetry on S3. The simplest case corresponds to the unfrustrated field tangent to the Hopf fibration. The excited states are labelled by an integral winding number m. For each value of m we derive a lower bound for the energy.
R Dandoloff, R Mosseri
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Twisted bilayer graphene’s gallery of phases
Physics TodayThe simultaneous occurrence of exotic phases, and the ability to easily tune them, has positioned magic-angle twisted bilayer graphene as one of the richest materials platforms in condensed-matter physics.
B. Andrei Bernevig, Dmitri K. Efetov
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Evidence for An Hexagonal Phase in Twisted Nematics
Molecular Crystals and Liquid Crystals, 1978Abstract Sequences of microscopic photographies show different behaviors during the isotropic-cholesteric transition in a binary diagram untwisted nematic-cholesterol ester. For certain conditions, a mosaǐc texture arises between the isotropic liquid and the focal-conic texture, the germination of which gives evidence for an hexagonal symmetry.
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Twist Grain Boundary (TGB) Phases
2007Chirality in self-organizing media can yield a variety of novel mesophases with unique properties and structures. At high levels of chirality, however, non-linear effects come into play. The effects of chirality in self-assembled structures can compete successfully with those of conventional self-assembling properties to yield frustrated structures ...
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