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arXiv · 1504.03619

Chiral structures and defects of lyotropic chromonic liquid crystals induced by saddle-splay elasticity

Zoey S. Davidson·Louis Kang·Joonwoo Jeong·Tim Still·Peter J. Collings·Tom C. Lubensky·A. G. Yodh
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Abstract

An experimental and theoretical study of lyotropic chromonic liquid crystals (LCLCs) confined in cylinders with degenerate planar boundary conditions elucidates LCLC director configurations. When the Frank saddle-splay modulus is more than twice the twist modulus, the ground state adopts an inhomogeneous escaped-twisted configuration. Analysis of the configuration yields a large saddle-splay modulus, which violates Ericksen inequalities but not thermodynamic stability. Lastly, we observe point defects between opposite-handed domains and explain a preference for point defects over domain walls.

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Zoey S. Davidson, Louis Kang, Joonwoo Jeong, Tim Still, Peter J. Collings, Tom C. Lubensky, A. G. Yodh. 2015-05-07. Chiral structures and defects of lyotropic chromonic liquid crystals induced by saddle-splay elasticity. https://doi.org/10.1103/physreve.91.050501

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