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Title: Small-angle light scattering symmetry breaking in polymer-dispersed liquid crystal films with inhomogeneous electrically controlled interface anchoring

Abstract

We have described the method of analyzing and reporting on the results of calculation of the small-angle structure of radiation scattered by a polymer-dispersed liquid crystal film with electrically controlled interfacial anchoring. The method is based on the interference approximation of the wave scattering theory and the hard disk model. Scattering from an individual liquid crystal droplet has been described using the anomalous diffraction approximation extended to the case of droplets with uniform and nonuniform interface anchoring at the droplet–polymer boundary. The director field structure in an individual droplet is determined from the solution of the problem of minimizing the volume density of the free energy. The electrooptical effect of symmetry breaking in the angular distribution of scattered radiation has been analyzed. This effect means that the intensities of radiation scattered within angles +θ{sub s} and–θ{sub s} relative to the direction of illumination in the scattering plane can be different. The effect is of the interference origin and is associated with asymmetry of the phase shift of the wavefront of an incident wave from individual parts of the droplet, which appears due to asymmetry of the director field structure in the droplet, caused by nonuniform anchoring of liquid crystal moleculesmore » with the polymer on its surface. This effect is analyzed in the case of normal illumination of the film depending on the interfacial anchoring at the liquid crystal–polymer interface, the orientation of the optical axes of droplets, their concentration, sizes, anisometry, and polydispersity.« less

Authors:
;  [1];  [2];  [1]
  1. National Academy of Sciences of Belarus, Stepanov Institute of Physics (Belarus)
  2. Russian Academy of Sciences, Kirensky Institute of Physics, Federal Research Center “Krasnoyarsk Scientific Center,” Siberian Branch (Russian Federation)
Publication Date:
OSTI Identifier:
22617055
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 124; Journal Issue: 3; Other Information: Copyright (c) 2017 Pleiades Publishing, Inc.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANGULAR DISTRIBUTION; APPROXIMATIONS; ASYMMETRY; CONCENTRATION RATIO; DIFFRACTION; DROPLETS; FILMS; FREE ENERGY; ILLUMINANCE; INTERFACES; INTERFERENCE; LIGHT SCATTERING; LIQUID CRYSTALS; MAGNETIC DISKS; MOLECULES; PHASE SHIFT; POLYMERS; SURFACES; SYMMETRY BREAKING

Citation Formats

Loiko, V. A., E-mail: loiko@ifanbel.bas-net.by, Konkolovich, A. V., Zyryanov, V. Ya., and Miskevich, A. A. Small-angle light scattering symmetry breaking in polymer-dispersed liquid crystal films with inhomogeneous electrically controlled interface anchoring. United States: N. p., 2017. Web. doi:10.1134/S1063776117020133.
Loiko, V. A., E-mail: loiko@ifanbel.bas-net.by, Konkolovich, A. V., Zyryanov, V. Ya., & Miskevich, A. A. Small-angle light scattering symmetry breaking in polymer-dispersed liquid crystal films with inhomogeneous electrically controlled interface anchoring. United States. doi:10.1134/S1063776117020133.
Loiko, V. A., E-mail: loiko@ifanbel.bas-net.by, Konkolovich, A. V., Zyryanov, V. Ya., and Miskevich, A. A. Wed . "Small-angle light scattering symmetry breaking in polymer-dispersed liquid crystal films with inhomogeneous electrically controlled interface anchoring". United States. doi:10.1134/S1063776117020133.
@article{osti_22617055,
title = {Small-angle light scattering symmetry breaking in polymer-dispersed liquid crystal films with inhomogeneous electrically controlled interface anchoring},
author = {Loiko, V. A., E-mail: loiko@ifanbel.bas-net.by and Konkolovich, A. V. and Zyryanov, V. Ya. and Miskevich, A. A.},
abstractNote = {We have described the method of analyzing and reporting on the results of calculation of the small-angle structure of radiation scattered by a polymer-dispersed liquid crystal film with electrically controlled interfacial anchoring. The method is based on the interference approximation of the wave scattering theory and the hard disk model. Scattering from an individual liquid crystal droplet has been described using the anomalous diffraction approximation extended to the case of droplets with uniform and nonuniform interface anchoring at the droplet–polymer boundary. The director field structure in an individual droplet is determined from the solution of the problem of minimizing the volume density of the free energy. The electrooptical effect of symmetry breaking in the angular distribution of scattered radiation has been analyzed. This effect means that the intensities of radiation scattered within angles +θ{sub s} and–θ{sub s} relative to the direction of illumination in the scattering plane can be different. The effect is of the interference origin and is associated with asymmetry of the phase shift of the wavefront of an incident wave from individual parts of the droplet, which appears due to asymmetry of the director field structure in the droplet, caused by nonuniform anchoring of liquid crystal molecules with the polymer on its surface. This effect is analyzed in the case of normal illumination of the film depending on the interfacial anchoring at the liquid crystal–polymer interface, the orientation of the optical axes of droplets, their concentration, sizes, anisometry, and polydispersity.},
doi = {10.1134/S1063776117020133},
journal = {Journal of Experimental and Theoretical Physics},
number = 3,
volume = 124,
place = {United States},
year = {Wed Mar 15 00:00:00 EDT 2017},
month = {Wed Mar 15 00:00:00 EDT 2017}
}
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