Bubble Domain Texture

In long-pitch nemato-cholesteric mixtures oriented homeotropically by cell walls, the bubble domain texture is often observed. A careful investigation of the director distribution in the bubble and striped (fingerprint) domains has been carried out in [3]. 

If the cell walls are treated to produce a homeotropic orientation in a cholesteric liquid crystal with As < 0, for a particular relation between the thickness and the helical pitch (1 < Po/d < 2) a new texture appears under the influence of the electric fleld. These are the bubble domains [77] mentioned in Section 6.1.1. When there is no field present the liquid crystal has a homeotropic nematic structure, since the helix is untwisted by the walls. The application of a low-frequency field induces an electrohydrodynamic instability. After the removal of the field a new stable texture appears in the form of cholesteric bubbles dispersed through the homeotropic nematic phase. Thus a memory is created, while erasure of the information can be performed either by a high-frequency field or by the mechanical... 

Bridgman flexible bellows with slide wire 369 Brillouin scattering 719-726 broken aspects, textures 439 bubble domains, ultrasonic fields 557 building blocks, synthesis 98 bulk fluids, molecular modelling 77 bulk SHG, optical properties 577 bulk systems, large-scale simulation 83 buoyancy method, density measurements 332 Burgers vectors, defects 425,447... 

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