KTA Crystal
KTA (Potassium Titanyle Arsenate, KTiOAsO4 ) is a nonlinear optical crystal similar to KTP in which atom P is replaced by As. It has good non-linear optical and electro-optical properties, e.g. significantly reduced absorption in band range of 2.0-5.0 µm, broad angular and temperature bandwidth, low dielectric constants.
Compared with KTP, the main advantages of KTA include: higher second-order nonlinear coefficient, longer IR cut-off wavelength, and less absorption at 3.5 µm. KTA also has lower ionic conductivity than that of KTP, which results in a higher laser induced damage threshold.
KTA is very popularly used for Optical Parametric Oscillation (OPO) application which gives high energy conversion efficiency (above 50%) of tunable laser radiation in solid lasers.
Contact us for the best solution for your application of KTA crystals.
WISOPTIC Advantages - KTA
• High homogeneity, excellent internal quality
• Top quality of surface polishing
• Large block for various size (e.g. 10x10x30mm3, 5x5x35mm3)
• Large nonlinear coefficient, high conversion efficiency
• Broad transparency range, large temperature matching width
• AR coatings for wave range from visual light to 3300 nm
• Very competitive price, quick delivery
WISOPTIC Standard Specifications* - KTA
| Dimension Tolerance | ± 0.1 mm |
| Cutting Angle Tolerance | < ± 0.25° |
| Flatness | < λ/8 @ 632.8 nm |
| Surface Quality | < 10/5 [S/D] |
| Parallelism | < 20” |
| Perpendicularity | ≤ 5' |
| Chamfer | ≤ 0.2mm @ 45° |
| Transmitted Wavefront Distortion | < λ/8 @ 632.8 nm |
| Clear Aperture | > 90% central area |
| Coating | AR@1064nm(R<0.2%) & 1533nm(R<0.5%) & 3475nm(R<9%) or upon request |
| Laser Damage Threshold | 500 MW/cm2 for 1064nm, 10ns, 10Hz (AR-coated) |
| * Products with special requirement upon request. | |
Main Features - KTA
• High nonlinear coefficient, high electro-optical coefficient
• Wide acceptance angle, small wall-off angle
• Broad transparency range, large temperature matching width
• Small dielectric constant, low ionic conductivity
• Lower absorption in 3-4 µm spectrum range than that of KTP
• High laser damage threshold
Primary Applications - KTA
• OPO for mid IR generation – up to 4 µm
• Sum and Difference Frequency Generation in mid IR range
• Electro-optical modulation and Q-switching
• Frequency doubling (SHG @1083nm-3789nm).
Physical Properties - KTA
| Chemical formula | KTiOAsO4 |
| Crystal structure | Orthorhombic |
| Point group | mm2 |
| Space group | Pna21 |
| Lattice constants | a=13.103 Å, b=6.558 Å, c=10.746 Å |
| Density | 3.454 g/cm3 |
| Melting point | 1130 °C |
| Curie temperature | 881 °C |
| Mohs hardness | 5 |
| Thermal conductivity | k1=1.8 W/(m·K), k2=1.9 W/(m·K), k3=2.1 W/(m·K) |
| Hygroscopicity | non-hygroscopic |
Optical Properties- KTA
| Transparency region (at “0” transmittance level) |
350-5300 nm | ||
| Refractive indices (@632.8 nm) | nx | ny | nz |
| 1.8083 | 1.8142 | 1.9048 | |
| Linear absorption coefficients (@532 nm) |
α = 0.005/cm | ||
|
NLO coefficients (@1064 nm) |
d15=2.3 pm/V, d24=3.64 pm/V, d31=2.5 pm/V, d32=4.2 pm/V, d33=16.2 pm/V |
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Electro-optic coefficients |
r13 |
r23 |
r33 |
| 11.5 ± 1.2 pm/V | 15.4 ± 1.5 pm/V | 37.5 ± 3.8 pm/V | |
