| Autor: |
J. Ruth, V. Sergan, Yu. Reznikov, Philip J. Bos, James E. Anderson, P. Watson |
| Rok vydání: |
1999 |
| Předmět: |
|
| Zdroj: |
Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals. 330:95-100 |
| ISSN: |
1058-725X |
| DOI: |
10.1080/10587259908025580 |
| Popis: |
We have investigated the relaxation process from a homeotropic structure to the planar one in a cholesteric liquid crystal. The relaxation occurs after switching off the electric field. We have developed a new experimental photography technique with a time resolution of about 20μs and applied it to the investigation of textural changes during the transition. After the liquid crystal goes through a defect-free transient planar structure, the development of the cholesteric helices occurs in two stages. Direct observations have shown that formation of the final equilibrium state involves a nucleation process. We used optical retroreflection spectroscopy and measurement of light scattering to observe changes of the cholesteric pitch and orientation of helices as well as the size of domains in time for various treatments of the glass substrates. We have also proposed a theoretical model that describes the experimental data satisfactorily. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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