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A Discotic Disguised as a Smectic: A Hybrid Columnar Bragg Glass

Karl Saunders·Leo Radzihovsky·John Toner
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Abstract

We show that discotics, lying deep in the columnar phase, can exhibit an x-ray scattering pattern which mimics that of a somewhat unusual smectic liquid crystal. This exotic, new glassy phase of columnar liquid crystals, which we call a ``hybrid columnar Bragg glass'', can be achieved by confining a columnar liquid crystal in an anisotropic random environment of e.g., strained aerogel. Long-ranged orientational order in this phase makes {\em single domain} x-ray scattering possible, from which a wealth of information could be extracted. We give detailed quantitative predictions for the scattering pattern in addition to exponents characterizing anomalous elasticity of the system.

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Karl Saunders, Leo Radzihovsky, John Toner. 2000-10-14. A Discotic Disguised as a Smectic: A Hybrid Columnar Bragg Glass. https://doi.org/10.1103/physrevlett.85.4309

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