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arXiv · 1210.1431

Electro-optical memory of a nematic liquid crystal doped by multi-walled carbon nanotubes

L. Dolgov·O. Yaroshchuk·S. Tomylko·N. Lebovka
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Abstract

A pronounced irreversible electro-optical response (memory effect) has been recently observed for nematic liquid crystal (LC) EBBA doped by multi-walled carbon nanotubes (MWCNTs) near the percolation threshold of the MWCNTs (0.02-0.05 wt. %). It is caused by irreversible homeotropic-to-planar reorientation of LC in an electric field. This feature is explained by electro-hydrodynamically stimulated dispergation of MWCNTs in LC and by the formation of a percolation MWCNT network which acts as a spatially distributed surface stabilizing the planar state of the LC. This mechanism is confirmed by the absence of memory in the EBBA/MWCNT composites, whose original structure is fixed by a polymer. The observed effect suggests new operation modes for the memory type and bistable LC devices, as well as a method for \textit{in situ} dispergation of carbon nanotubes in LC cells.

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L. Dolgov, O. Yaroshchuk, S. Tomylko, N. Lebovka. 2012-10-04. Electro-optical memory of a nematic liquid crystal doped by multi-walled carbon nanotubes. https://doi.org/10.5488/cmp.15.33401

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