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arXiv · 2606.09211

Evaluation of nonlinear optical coefficients in uniformly aligned dioxane-based ferroelectric nematic liquid crystals using second harmonic generation

Hirokazu Kamifuji·Jigen Furukawa·Kazuma Nakajima·Hirotsugu Kikuchi·Kenjiro Fukuda·Masanori Ozaki
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Abstract

Ferroelectric nematic liquid crystals (FNLCs) are promising soft platforms for nonlinear optics, but quantitative determination of their second-order nonlinear optical coefficients has been hindered by limited alignment control. Here, polarization-resolved second-harmonic generation (SHG) measurements on a uniformly aligned dioxane-based FNLC, combined with Jones-matrix simulations, enable determination of all principal tensor components. The resulting tensor is consistent with the expected $C_{\infty v}$ and Kleinman symmetries, while the measured coefficients cannot be explained by a simple sum of molecular first hyperpolarizabilities. These results provide a quantitative basis for understanding nonlinear optical responses and guiding the design of FNLC-based nonlinear optical materials and devices.

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Hirokazu Kamifuji, Jigen Furukawa, Kazuma Nakajima, Hirotsugu Kikuchi, Kenjiro Fukuda, Masanori Ozaki. 2026-06-08. Evaluation of nonlinear optical coefficients in uniformly aligned dioxane-based ferroelectric nematic liquid crystals using second harmonic generation. https://arxiv.org/abs/2606.09211

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