"Electro-Optics of a Smectic Liquid Crystal Doped with Nanoparticles"
The liquid crystal CCN-47 exhibits Smectic A phase between 20 and 31 deg C after which it goes through the nematic phase. The smectic A phase is very interesting from the point of view that the cells can spontaneously form defects known as focal conics. When an electric field is applied in the appropriate geometry, these focal conic domains nucleate and grow to form a different phase.
The dynamics of the nucleation process is monitored as a function of time using time lapse video techniques. A careful study of the transition from focal conic domain to the nucleated domain structure is being done as a function of temperature to get a clear understanding of the nature of phases involved in this material. There are indications of very strong pre-transitional effects at temperatures closer to the smectic-nematic transition.
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