Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics · 1994 · 28 citations · 15 references
Quantum LiquidCrystal StructureComplex Director DeformationTwist Fréedericksz TransitionTransient StructuresPhysicsTwist Fr\'eedericksz TransitionEngineeringSelf-assemblyCrystal MaterialCondensed Matter PhysicsApplied PhysicsLiquid Crystalline ElastomerSimple LiquidSoft MatterCrystal FormationCrystallographyBiophysics
We have investigated the evolution of transient structures in the twist Fr\'eedericksz transition of low-molecular-weight nematic liquid crystals. Planarly aligned cells have been exposed to an in-plane external magnetic field perpendicular to the initial director orientation. The formation of periodic structures was studied by conventional microscopy. We observed a complex director deformation showing an induced out-of-plane tilt. We describe the formation of periodic long-term stable twist-bend inversion walls which can be observed up to several hours after their appearance. The wavelengths of the structures determined experimentally are discussed and compared to theoretical predictions.
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