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arXiv · 2408.04225

Giant electro-optic and elasto-optic effects in ferroelectric NbOI$_{2}$

Zhenlong Zhang·Xuehan Di·Charles Paillard·Laurent Bellaiche·Zhijun Jiang
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Abstract

First-principles calculations are performed to investigate the electro-optic (EO) and elasto-optic effects of the three-dimensional (bulk) and two-dimensional (monolayer) ferroelectric NbOI$_{2}$. Remarkably large linear EO and elasto-optic coefficients are discovered in both systems, when under stress-free conditions. We further found that the EO responses of bulk and monolayer NbOI$_{2}$ can be further enhanced with epitaxial strain, because of a strain-driven ferroelectric-to-paraelectric transition that originates from the softening of some polar optical modes. Our findings thus point out that NbOI$_{2}$, as well as other niobium oxide dihalides are highly promising for paving the way for potentially efficient nonlinear optical device applications.

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Zhenlong Zhang, Xuehan Di, Charles Paillard, Laurent Bellaiche, Zhijun Jiang. 2024-08-08. Giant electro-optic and elasto-optic effects in ferroelectric NbOI$_{2}$. https://doi.org/10.1103/physrevb.110.l100101

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