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Shear Alignment and Instability of Smectic Phases

Mark Goulian·Scott T. Milner
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Abstract

We consider the shear flow of well-aligned one-component smectic phases, such as thermotropic smectics and lamellar diblock copolymers, below the critical region. We show that, as a result of thermal fluctuations of the layers, parallel ($c$) alignment is generically unstable and perpendicular ($a$) alignment is stable against long-wavelength undulations. We also find, surprisingly, that both $a$ and $c$ are stable for a narrow window of values for the anisotropic viscosity.

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Mark Goulian, Scott T. Milner. 1995-01-17. Shear Alignment and Instability of Smectic Phases. https://doi.org/10.1103/physrevlett.74.1775

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