Potassium Yttrium Tungstate (KYWO₄₂) is a high-performance Raman crystal used extensively in advanced laser systems. KYW crystals exhibit broad transparency, ranging from 350 nm to 5.5 µm, making them suitable for various laser-based applications. Their high thermal conductivity, which is approximately three times higher than barium nitrate, ensures efficient heat dissipation during high-power operations.
KYW are specifically designed for Raman frequency shifting, featuring two large Raman modes at 765 cm⁻¹ and 905 cm⁻¹. The crystals offer good mechanical properties, high optical damage thresholds, and superior radiation frequency tuning capabilities. These properties make KYW ideal for high-intensity laser applications.
KYW crystals are widely utilized in:
| Property | Value |
|---|---|
| Chemical Formula | K(YWO₄)₂ |
| Crystal Structure | Monoclinic, C2/c |
| Lattice Parameters | a = 10.64 Å, b = 10.32 Å, c = 7.55 Å |
| Density | 6.61 g/cm³ |
| Mohs Hardness | 4–5 |
| Transparency Range | 0.35 µm – 5.5 µm |
| Thermal Conductivity (average) | 3.3 W/m·K |
| dn/dT (Refractive Index Temperature Coefficient) | dn/dTₓ = -1.4 × 10⁻⁴ K⁻¹ dn/dTᵧ = -8.9 × 10⁻⁵ K⁻¹ dn/dT𝓏 = -1.2 × 10⁻⁴ K⁻¹ |
| Refractive Indices (1064 nm) | nₓ = 1.9868, nᵧ = 2.0055, n𝓏 = 2.0367 |
| Optical Property | Value |
|---|---|
| Raman Frequency Shifts | 765 cm⁻¹ (E |
| Raman Linewidth | 5.4 cm⁻¹ (polarization E |
| Raman Gain Coefficient | 3.6 cm/GW (steady-state regime at 1064 nm) |
| Specification | Value |
|---|---|
| Orientation | b-cut |
| Clear Aperture | >90% |
| Face Dimensions Tolerance | +0/-0.1 mm |
| Length Tolerance | ±0.1 mm |
| Parallelism Error | <20 arcsec |
| Perpendicularity Error | <10 arcmin |
| Surface Flatness | <λ/8 @ 632.8 nm |
| Surface Quality | 10-5 S-D |
| Wavefront Distortion | <λ/8 @ 632.8 nm |
The transmission spectrum of KYW crystals spans from 350 nm to 5.5 µm, offering high transparency across a broad wavelength range, crucial for Raman laser operations. Additional data or graphs available upon request.
| Face Dimensions | Length | Coatings | Price (USD) |
|---|---|---|---|
| 15 mm x 15 mm | 5 mm | Uncoated | 440 |
| 15 mm x 15 mm | 10 mm | AR(450–800 nm) | 600 |
| 5 mm x 5 mm | 30 mm | AR(450–800 nm) | 780 |
| 8 mm x 8 mm | 50 mm | AR(450–800 nm) | 1120 |
| Customization | Any | Per customer request | TBD |
