LiNbO3 (Lithium Niobate) Crystals are one of the most versatile crystals with their unique electro-optic, piezo-electric properties. In the area of nonlinear optics, the diversified usages of LiNbO3 include frequency conversion, electro-optic modulation, SAW wafers, etc. It is an excellent medium for SHG at wavelengths > 1µm, Optical Parametric Oscillation (OPO), Optical Parametric Amplifiers (OPA), and generation of tunable infrared output by difference frequency mixing (DFM). LiNbO3 features broad spectral transmission (0.3-5.2 micro) ranging from the Visible to MWIR wavelengths and a high laser-induced damage threshold. The large nonlinearities of LiNbO3 also suggest that higher effective nonlinear coefficients (d_eff) could be achieved at lower power intensities.

Compared with LiNbO3, MgO:LiNbO3 (Magnesium Doped Lithium Niobate) Crystal has a higher optical damage threshold than normal lithium niobate and therefore should be considered for high-power applications. LiNbO3 is susceptible to photorefractive damage, which is a detrimental trait for the conversion of frequencies. The problem could be alleviated using MgO-doped lithium niobate, which is less prone to optical damage. In addition, MgO: LiNbO3 exhibits its particular advantages for Non-Critical Phase Matched (NCPM) Second Harmonic Generation/Doubling Frequencies (SHG) at room temperature, and SFG.

Due to its large Electro-Optic (E-O) coefficients, LiNbO3 crystals are also the ideal medium for manufacturing EO modulators.

Shanghai North Optics provides custom LiNbO3 and MgO(0.6~1.0%)/MgO(5mol%) Doped LiNbO3 Crystals for Nonlinear Optical Processing. The crystals are available in the form of blanks, or laser-grade-polished/coated. Modules with electrodes are available upon your request. Besides, EO Grade LiNbO3/MgO:LiNbO3 Crystals, and Periodical Poled Lithium Niobate (PPLN) Crystals for Quasi Phase Matched (QPM) conversion of frequencies, fabricated Y128/Y36/Y/Z-Cut LiNbO3 SAW Wafers are also accessible in North Optics. 

Application of Lithium Niobate and MgO Doped Lithium Niobate:

1. Second Harmonic Generation, in particular for 1064nm Nd:YAG lasers and low-power laser diodes between 1.3-1.55 micros

2. OPO for Generation of the tunable laser output in the IR range

3. MgO:LiNbO3 has the additional advantage of higher resistance to photorefractive damage, therefore could handle high-power applications

4. MgO:LiNbO3 could also realize Non-critical phase-matched conversion of frequencies under room temperature, saving the cost of a crystal oven for maintaining temperatures.

5. Electro-optic Modulation. Lithium Niobate is an ideal material to be incorporated into EO modulators such as pockels cells, with the virtues of low half-wave/quarter-wave voltage, and low residential birefringence.

6. PPLN crystals are superior for Quasi-Phase-Matched conversion of frequencies, and optical parametric oscillation. Compared to Critical Phase Matching based on the birefringence of materials, QPM is less a victim of the spatial walk-off, and the d_eff could be utilized more to the full.