Experimental evidence for helical instability of screw dislocation lines in a smectic A phase
- 1 January 1984
- journal article
- Published by EDP Sciences in Journal de Physique Lettres
- Vol. 45 (7) , 319-328
- https://doi.org/10.1051/jphyslet:01984004507031900
Abstract
When submitted to a constant deformation, homeotropic samples of Sm A relax towards equilibrium with two time constants, one of them (shorter) characteristic of the climb of edge dislocations of the grain boundary which in practice is always found in the middle plane of the sample, the other one (longer) characteristic of a sequence of helical instabilities of the screw dislocations which, although metastable, are always present in the sample. This instability occurs for an integral number of pitches of the helix in the thickness of the sample. Experiment matches with the theory developed in [9] for static deformations and extended here to the dynamical regimeKeywords
This publication has 8 references indexed in Scilit:
- Plastic behavior and polymorphism of smectic liquid crystalsJournal de Chimie Physique et de Physico-Chimie Biologique, 1983
- Dynamic Aspects of the Undulation Instability in Smectic A Liquid CrystalsMolecular Crystals and Liquid Crystals, 1983
- Rheological behaviour of a smectic A liquid crystal under layer compressionJournal de Physique Lettres, 1983
- Forces due to structure in a thin liquid crystal filmJournal de Physique, 1981
- On static helical instabilities of screw dislocations in a SmA phase and on their consequence on plasticityJournal de Physique, 1981
- Critical behaviour of second sound near the smectic A nematic phase transitionJournal de Physique, 1981
- Dislocation Effects on the Viscoelastic Properties of a Smectic A Liquid CrystalMolecular Crystals and Liquid Crystals, 1977
- Defect structures in lyotropic smectic phases revealed by freeze-fracture electron microscopyPhilosophical Magazine, 1977