Lithium Niobate (LiNbO₃), commonly referred to as LN, is one of the most important nonlinear optical crystals in modern photonics. It is widely recognized for its exceptional electro-optic (EO), nonlinear optical (NLO), piezoelectric, and acousto-optic properties, making it a cornerstone material for laser systems, optical modulation, and integrated photonics.
LN crystals are extensively used for frequency conversion, optical parametric oscillation, and high-speed optical modulation, particularly in applications operating at and above 1064 nm.
Mechanical & Structural Properties
| Parameter | Value |
|---|---|
| Density | 4.64 g·cm⁻³ |
| Melting Point | 1253 °C |
| Curie Temperature | 1140 °C |
| Mohs Hardness | 5 |
| Crystal Structure | Trigonal System |
| Lattice Constants | a = 5.148 Å, c = 13.863 Å |
| Elastic Stiffness | CE₁₁ = 2.33 × 10¹¹ N·m⁻² CE₃₃ = 2.77 × 10¹¹ N·m⁻² |
Thermal & Electrical Properties
| Parameter | Value |
|---|---|
| Thermal Expansion | 2.0 × 10⁻⁶ K⁻¹ (‖ a-axis @25 °C) 2.2 × 10⁻⁶ K⁻¹ (‖ c-axis @25 °C) |
| Thermal Conductivity | 38 W·m⁻¹·K⁻¹ @25 °C |
| Electrical Resistivity | 2 × 10⁶ Ω·cm @200 °C |
| Piezoelectric Strain Constant | D₂₂ = 2.04 × 10⁻¹¹ C·N⁻¹ D₃₃ = 19.22 × 10⁻¹¹ C·N⁻¹ |
Optical & Electro-Optical Properties
| Parameter | Value |
|---|---|
| Transparency Range | 420 – 5200 nm |
| Optical Homogeneity | ~5 × 10⁻⁵ cm⁻¹ |
| Refractive Indices | nₑ = 2.146, nₒ = 2.220 @1300 nm nₑ = 2.156, nₒ = 2.232 @1064 nm nₑ = 2.203, nₒ = 2.286 @632.8 nm |
| NLO Coefficients | d₃₃ = 86 × d₃₆ (KDP) d₃₁ = 11.6 × d₃₆ (KDP) d₂₂ = 5.6 × d₃₆ (KDP) |
| Effective NLO Coefficients | dₑff(I) = d₃₁sinθ − d₂₂cosθsin3φ dₑff(II) = d₂₂cos2θcos3φ |
| Electro-Optic Coefficients | rT₃₃ = 32, rS₃₃ = 31 rT₃₁ = 10, rS₃₁ = 8.6 rT₂₂ = 6.8, rS₂₂ = 3.4 |
| Half-Wave Voltage | 3.03 kV (E ‖ z, light ⟂ z) 4.02 kV (E ‖ x or y, light ‖ z) |
Standard Manufacturing Specifications
| Item | Specification |
|---|---|
| Dimension Tolerance | W × H ±0.1 mm, L +0.2 / −0.1 mm |
| Angular Tolerance | Δθ ≤ 0.25°, Δφ ≤ 0.25° |
| Parallelism | < 20 arc sec |
| Perpendicularity | < 5 arc min |
| Chamfer | 0.1 mm × 45° |
| Clear Aperture | ≥ 90% |
| Scratch & Dig | 20/10 or better |
| Surface Flatness | λ/8 @ 633 nm |
| Wavefront Distortion | λ/8 @ 633 nm |
| Damage Threshold | 100 MW·cm⁻² (@1064 nm, 10 ns, 10 Hz) |
Key Advantages
- High nonlinear optical efficiency for SHG, OPO, and QPM devices
- Large electro-optic coefficients for fast and stable optical modulation
- Wide transparency range from visible to mid-infrared
- Excellent piezoelectric and acousto-optic performance
- Proven reliability in telecom, industrial, and research systems
Typical Applications
- Electro-Optic Modulators & Switches: Phase modulators, intensity modulators, Pockels cells, and Q-switches
- Frequency Conversion: Frequency doubling for wavelengths >1 µm and nonlinear mixing processes
- Optical Parametric Oscillators (OPOs): Pumped at 1064 nm for tunable laser generation
- Integrated Photonics & Waveguides: Substrates for photonic integrated circuits and QPM devices
- SAW Devices & Sensors: Surface acoustic wave filters, oscillators, and precision sensors
Shape Optics Capabilities
Shape Optics supplies high-quality Lithium Niobate crystals for both standard and custom requirements.
Available Configurations
- Maximum size: up to 10 × 10 × 20 mm
- Thickness / length: 0.02 mm – 20 mm
- Crystal orientation & cutting: custom on request
- Optical coatings: available upon request
With over 20 years of experience, Shape Optics offers advanced manufacturing, precision polishing, and in-house coating solutions across the UV–NIR spectrum. We work with premium optical materials such as fused silica, Germanium, ZnSe, and more, ensuring consistent quality, fast lead times, and full compliance with international standards.
For reliable, high-performance lithium niobate solutions, contact Shape Optics to discuss your application or request a quotation.