21 °C. Extraordinary ray (e). Congruently grown lithium niobate.
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Lithium niobate (LiNbO3) is a ferroelectric material with excellent electro-optic, piezoelectric, and nonlinear optical properties. It is widely used in integrated optics, optoelectronic devices, and telecommunication applications. LiNbO3 crystals are often employed in modulators, switches, waveguide devices, and frequency doublers. Due to its strong Pockels effect, it is a popular choice for Q-switching in solid-state lasers and is a key material in the fabrication of surface acoustic wave (SAW) devices. The material is generally transparent in the wide wavelength range from the near-infrared to the ultraviolet, making it versatile for various optical applications.