The chiral-flexoelectrooptic effect in a Uniform Lying Helix (ULH) configuration provides a sub-millisecond in-plane rotation of the optic axis with the application of a transverse field. This enables displays with a wide viewing angle without costly in-plane-type electrodes. The salient challenge is one of alignment of the ULH, which is not topologically compatible with uniform alignment surface treatments. Here, we create a micro-grooved surface structure with features on the micron scale by using a replica-moulding technique. When the cell is assembled, the micro-grooves create channels, and using surface-energy considerations, we explain how and show experimentally that the channels align a cholesteric material in the ULH geometry with the helicoidal axis oriented parallel to the channels. The resultant alignment provides a high level of contrast between crossed polarizers and exhibits an electrooptic response with a switching time of the order of tens of microseconds.

We discuss the static configuration of a smectic A liquid crystal subject to an edge dislocation under the assumption that the director and layer normal fields ([Formula: see text] and [Formula: see text], respectively) defining the smectic arrangement are not, in general, equivalent. After constructing the free energy for the smectic, we obtain exact solutions to the equilibrium equations which result from its minimisation at quadratic order in the variables which describe the distortion, and hence a complete description of the smectic configuration across the domain of the sample. We also examine the effect of relaxing the constraint [Formula: see text] for different values of the constants which characterise the response of the material to distortions, and compare these results with the 'classical' case considered by previous authors, in which equivalence of [Formula: see text] and [Formula: see text] is enforced.

Results of theoretical investigations into the behaviour of a shear wave at the boundary between an isotropic solid and a smectic A liquid crystal are presented. These results track the subsequent response of the smectic to the refracted wave. Using the techniques of Landau and Lifshitz for sound in isotropic fluids [1], we extend the results for smectic C by Gill and Leslie [2] and perform the analogous calculations for a sample of smectic A using the dynamic theory of Stewart [3]. These calculations enable a comparison between the results for smectic A and an extension, by the present authors, to the known results for smectic C.Motivated by the work of Auernhammer, Brand, and Pleiner [4,5], mechanisms for determining the impact of perturbations upon the modes of response behaviour will be analysed, with plots demonstrating the amplitudes of these waves relative to that of the incident wave displayed for a range of typical physical parameters characteristic to smectic C and smectic A.

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