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arXiv · 2410.22441

Microsecond electro-optic switching in the nematic phase of a ferroelectric nematic liquid crystal

Kamal Thapa·Sathyanarayana Paladugu·Oleg D. Lavrentovich
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Abstract

Nematic liquid crystals exhibit nanosecond electro-optic response to an applied electric field which modifies the degree of orientational order without realigning the molecular orientation. However, this nanosecond electrically-modified order parameter (NEMOP) effect requires high driving fields, on the order of 100 V/um for a modest birefringence change of 0.01. In this work, we demonstrate that a nematic phase of the recently discovered ferroelectric nematic materials exhibits a robust and fast electro-optic response. Namely, a relatively weak field of 20 V/um changes the birefringence by 0.04 with field-on and-off times around 1 us. This microsecond electrically modified order parameter (MEMOP) effect shows a greatly improved figure of merit when compared to other electro-optical switching modes in liquid crystals, including the conventional Frederiks effect, and has a potential for applications in fast electro-optical devices such as phase modulators, optical shutters, displays, and beam steerers.

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Kamal Thapa, Sathyanarayana Paladugu, Oleg D. Lavrentovich. 2024-10-29. Microsecond electro-optic switching in the nematic phase of a ferroelectric nematic liquid crystal. https://doi.org/10.1364/oe.541317

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