KTA Crystals
What Are KTA Crystals?
![Fig 1. Typical picture of the KTA crystal visualized along [010] direction.](/upload/image/products-1-1-10-kta-crystals-1.jpg)
Fig 1. Photo of a KTA crystal along [010]. [1]
Potassium titanyl arsenate (KTA, KTiOAsO4) is a nonlinear optical crystal similar to KTP but with much lower absorption and a smaller walk-off angle, and is especially useful in high-power and long-wavelength applications. KTA has a wide transparency range, extending into the mid-infrared, highly efficient nonlinear coefficients, and good electro-optic properties.
KTA is employed in optical parametric oscillators (OPOs), optical parametric amplifiers (OPAs), and difference-frequency generation (DFG) for tunable infrared sources because of its broad angular and temperature acceptance bandwidths, low absorption coefficients, and high damage threshold.
At Alfa Chemistry, we employ advanced crystal growth technologies to produce high-quality KTA crystals that meet the exacting demands of infrared applications across medical, and scientific fields.
Features
- Extended IR Transparency: 350 nm - 5300 nm, with superior performance in the 3-5 μm atmospheric window.
- Large Nonlinear Coefficients: d15 = 2.3 pm/V, d24 = 3.2 pm/V, d32 = 4.74 pm/V, d33 = 18.5 pm/V (@1064 nm).
- High Damage Threshold: >500 MW/cm2 (@1064 nm, 10 ns) for high power operation.
- Good Mechanical Properties: Has a hardness of 5.0 Mohs for processing and handling.
- High Optical Quality: Exhibits excellent homogeneity with low wavefront distortion.
- Wide Acceptance Angles: Has wide acceptance angles for flexible phase-matching.
- Non-hygroscopic: Non-hygroscopic and robust for handling and storage.
- Low Absorption: Lower absorption than KTP, especially in the 2–5 μm range.
- Low Dielectric Constant and Ionic Conductivity: Lower dielectric constant and ionic conductivity improve overall system stability and efficiency.
Specifications Product Options Applications
| Product Name | KTA Crystals |
| Catalog No. | OPTIX-0011 |
| Chemical Formula | KTiOAsO4 |
| Crystal Structure | Orthorhombic, Point group mm2 |
| Lattice Parameters | a = 13.125 Å, b = 6.5716 Å, c = 10.786 Å |
| Density | 3.454 g/cm3 |
| Mohs Hardness | ~ 5 |
| Melting Point | 1130 ℃ |
| Transmission Wavefront Distortion | λ/8 at 633nm |
| Angle Tolerance | ≤±0.25° |
| Dimension Tolerance | ±0.1mm |
| Parallelism | ≤20 arc sec |
| Perpendicularity | ≤15 arc min |
| Surface Quality (Scratch/Dig) | 10/5(MIL-PRF-13830B) |
| Flatness | λ/8 at 633nm |
| Hygroscopicity | No |
| Clear Aperture | 90% of central area |
| Coatings | AR-coating from visible to 3300 nm |
| Nonlinear Optical Properties |
| NLO Coefficient | d31= 2.76 pm/V, d32 = 4.74 pm/V
d33 = 18.5 pm/V, d15 = 2.3 pm/V
d24 = 3.2 pm/V |
| SHG Phase Matchable Range | 1083-3789nm |
| Damage Threshold | >500 MW/cm2 (@1064 nm, 10 ns) |
| Linear Optical Properties |
| Transparency Range | 350-5300 nm |
| Absorption Coefficients | <0.05%/cm at 1064 nm
<0.05%/cm at 1533 nm
<5%/cm at 3475 nm |
| Refractive Index | nx=1.90713, ny=2.15912, nz=2.14768 |
| Thermal and Electrical Properties |
| Thermal Conductivity | K1:1.8W/m/K, K2: 1.9W/m/K, K3: 2.1W/m/K |
| Electro-Optic Coefficients | r33=37.5 pm/V, r23=15.4 pm/V, r13=11.5 pm/V (low frequency) |
Note: The data provided is for reference purposes. We recommend consulting with our technical team to verify suitability for your application.
KTA Crystal Product Options
- Cut Orientations: X, Y, Z cuts or custom phase-matching cuts.
- Custom Dimensions: From small research samples (3 × 3 × 5 mm3) to large-aperture crystals (10 × 10 × 30 mm3 or 5 × 5 × 35 mm3).
- Surface Quality: Standard 10/5 scratch-dig; super-polish available for high-finesse cavities.
- Flatness & Parallelism: λ/8 flatness; <20 arcsec parallelism (tighter specs on request).
- Coatings: AR coatings optimized for pump, signal, and idler wavelengths (e.g., 1064 nm, 1.5–4 μm).
- Quality Grades: Research grade, production OEM grade, or high-damage-threshold grade with certified testing.
- Optical Parametric Oscillators (OPOs) for tunable mid-infrared sources.
- Optical Parametric Amplifiers (OPAs) for ultrafast and high-power lasers.
- Difference-Frequency Generation (DFG) for coherent mid-IR generation.
- Second-harmonic generation (SHG) of near-IR lasers.
- Nonlinear frequency conversion in high-power solid-state laser systems.
- Spectroscopy, medical diagnostics, environmental monitoring, and other applications requiring stable and efficient mid-IR light sources.
Why Choose Our KTA Crystals?
- Expert Crystal Growth & Fabrication: Decades of experience in producing high-quality nonlinear optical crystals.
- End-to-End Processing: In-house cutting, polishing, and coating to ensure precision and consistency.
- Custom Engineering Support: Tailored design recommendations for cut, size, and coating based on your pump and output requirements.
- High Quality Control Standards: Interferometric flatness testing, spectrophotometric transmission analysis, and laser damage threshold testing available.
- Flexible Supply Chain: From prototype crystals for R&D to volume production for OEMs.
- Global Service: Fast delivery, export documentation, and technical consultation for customers worldwide.
Reference
- Gao, Z. L., et al. Journal of Applied Physics 108.2 (2010).
