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Updated: Aug 7, 2026

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Disorder effect on the focus image of sonic crystals in air
Sheng Li1, Thomas F George, Liang-Shan Chen
1Office of the Chancellor and Center for Molecular Electronics, Department of Chemistry, University of Missouri-St. Louis, 63121, USA.
Abstract:
When acoustic waves propagate in two-dimensional sonic crystals composed of parallel rigid cylinders in air, anisotropic band gaps, such as a partial gap and deaf band, forbid the waves within certain frequency regions from propagating along certain directions, thus forming a stable imaging focus effect. If the introduced disorder has not destroyed the original anisotropic band gap, this unique effect still exists, although the focused image becomes blurred. Once the sample reaches complete disorder, the anisotropic band gap is destroyed, and this effect also disappears.
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