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arXiv · 1907.10227

Microsecond electro-optic switching of nematic liquid crystals with giant dielectric anisotropy

Bing-Xiang Li·Greta Babakhanova·Rui-Lin Xiao·Volodymyr Borshch·Simon Siemianowski·Sergij V. Shiyanovskii·Oleg D. Lavrentovich
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Abstract

Nematic liquid crystals exhibit a fast optical response when the applied electric field modifies the degree of order but does not change the direction of molecular orientation. The effect requires a relatively high electric field, on the order of 10^8 V/m for a field induced birefringence change of 0.01. To address this detrimental issue, this work explores electrically induced modification of the order parameter in a material with a giant dielectric anisotropy of +200. A relatively weak field 3X10^7 V/m causes a significant change of birefringence, by about 0.04. Both switching on and off times are ~10 microseconds. The effect is called a microsecond electrically modified order parameter (MEMOP) and can be used in electro-optical devices, such as fast electro-optic shutters, phase modulators, and beam-steerers that require microsecond response times.

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Bing-Xiang Li, Greta Babakhanova, Rui-Lin Xiao, Volodymyr Borshch, Simon Siemianowski, Sergij V. Shiyanovskii, Oleg D. Lavrentovich. 2019-07-24. Microsecond electro-optic switching of nematic liquid crystals with giant dielectric anisotropy. https://arxiv.org/abs/1907.10227

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