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SJ Elston

Publications and source records attributed to SJ Elston.

5 recordsLinked to original sources
PubMed2000

Shear-induced melting of smectic-A liquid crystals

A numerical and analytical analysis of shear-induced melting in smectic-A liquid crystals is presented. Based on a Landau expansion of the complex smectic order parameter, equations governing the phase and amplitude of the local density modulation are found. Numerically solving these equations indicates that for a range of parameter values a first-order transition, from a shear-stressed to a more relaxed state, is periodically encountered as the total shear is increased. Suitable approximations allow the analytic determination of certain characteristics of this first-order transition.

Journal Article↗
PubMed2000

Theoretical investigation into the effects of polar anchoring in antiferroelectric liquid crystal cells

We present a theoretical investigation into the effects of polar anchoring, which induces ferroelectric ordering close to the cell surfaces, in a liquid crystal cell containing an antiferroelectric liquid crystalline material. Our model includes effects due to finite polar and nonpolar anchoring, quadrupolar ordering and polarization self interaction. By minimizing the free energy of the system, we find parameter domains in which multiple zero-voltage solutions are stable. We find that these solutions may undergo thresholdless or hysteretic switching depending on the parameter values. In two instances, the presence of quadrupolar ordering or weak anchoring means that the cell must first be primed into the thresholdless state through a discontinuous transition from an initial antiferroelectric state.

Journal Article↗