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Updated: May 19, 2026

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Nonlinear optical grating diffraction in dye-doped blue-phase liquid crystals
1Electrical Engineering Department, Pennsylvania State University, University Park, Pennsylvania, USA. ick1@psu.edu
Abstract:
Low-power cw lasers are employed to study grating formation in blue-phase liquid crystals. We observed that undoped samples exhibit vanishingly small optical nonlinearities whereas methyl-red-dye doped samples produce strong nonlinear self-diffraction effects. The nonlinearities are attributed to director axis reorientation, disorder, and lattice distortion by the laser-excited dye molecules. The magnitude of the observed intensity-dependent index coefficient is in the range of 10(-4)-10(-3) cm2/Watt.
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