Smectics $A$ and $C$, and the Transition between them, in Uniaxial Disordered Environments

Leiming Chen; John Toner

doi:10.1103/physreve.79.031703

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Smectics $A$ and $C$, and the Transition between them, in Uniaxial Disordered Environments

Leiming Chen·John Toner

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Abstract

We present a theory of the elasticity and fluctuations of the Smectic A and C phases in uniaxial, anisotropic disordered environments, e.g., stretched aerogel. We find that, bizarrely, the low-temperature, lower-symmetry Smectic $C$ phase is less translationally ordered than the high-temperature, higher-symmetry Smectic $A$ phase, with short-ranged "$m=1$ Bragg glass" and algebraic "XY Bragg glass" order, respectively. The $AC$ phase transition belongs to a new universality class, whose fixed points and exponents we find in a $d=5-ε$ expansion. We give very detailed predictions for the very rich light scattering behavior of both phases, and the critical point.

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Leiming Chen, John Toner. 2008-09-11. Smectics $A$ and $C$, and the Transition between them, in Uniaxial Disordered Environments. https://doi.org/10.1103/physreve.79.031703

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