Description
Features：
• Large stimulated emission cross-section at laser wavelength;
• High absorption coefficient and wide bandwidth at pump wavelength;
• Low dependency on pump wavelength;
• Good thermal conductivity;
• Low lasing threshold and high slope efficiency;
• High laser-induced damage threshold;
• Strongly-polarized laser output.
Table 1. Basic Properties
| Crystal Structure | Tetragonal, space group I41/amd |
| Lattice Parameter | a = 7.21 Å, c = 6.35 Å |
| Lasing Transition | 4F3/2→4I11/2 |
| Lasing Wavelength | 1062.9 nm |
| Emission Cross Section (at 1064 nm) | 7.6 × 10-19 cm2 |
| Absorption Cross Section (at 808 nm) | 4.9 × 10-19 cm2 |
| Absorption Coefficient (at 808 nm) | 74 cm-1 |
| Index of Refractivity ( at 1064 nm) | no = 1.972, ne = 2.192 |
| Thermal Conductivity (<110＞) | 11.7 W/m/K |
| Density | 5.47 g/cm3 |
| Nd Dopant Concentration | 0.1%, 0.2%, 0.3%, 0.5%, 0.7%, 1.0%… |
Table 2. Material Properties: Comparing Nd:GdVO4 and Nd:YVO4
| Crystal | Nd:GdVO4 | Nd:YVO4 | ||
| Crystal Structure, Space Group | Tetragonal, I41/amd | Tetragonal, I41/amd | ||
| Lattice Parameter | a = 7.21 Å, c = 6.35 Å | a = 7.21 Å, c = 6.29 Å | ||
| Melting Temperature (℃) | 1780 | 1825 | ||
| Thermal Expansion @25 ℃, ×10-6/℃ | a | 1.5 | a | 4.43 |
| c | 7.3 | c | 11.4 | |
| Specific Heat @25 ℃, cal/mol·K | 32.6 | 24.6 | ||
| dn/dT, × 10-6 /℃ | 4.7 | 2.7 | ||
Table 3. Information Regarding Neodymium Laser Host Crystals
| Crystal | Nd:YVO4 | Nd:GdVO4 | Nd:YAG |
| Laser Wavelengths | 1064.3 nm, 1342.0 nm | 1062.9 nm, 1340 nm | 1064.2 nm, 1338.2 nm |
| Emission Bandwidth (linewidth at 1064 nm) | 0.8 nm | No data | 0.6 nm |
| Effective Laser Cross Section (emission cross section at 1064 nm) | 15.6 × 10-19 cm2 | 7.6 × 10-19 cm2 | 6.5 × 10-19 cm2 |
| Polarization | Parallel to c-axis | Parallel to c-axis | unpolarized |
| Fluorescence Lifetime with 1% Nd Doping | ~ 100 µs | ~ 95 µs | ~ 230 µs |
| Pump Wavelength | 808.5 nm | 808.4 nm | 807.5 nm |
| Peak Pump Absorption at 1% Doping | ~ 41 cm-1 | ~ 57 cm-1 | |
| Thermal Conductivity | 5.1 W/m/K | 11.7 W/m/K | 14 W/m/K |
| Doping Concentration Range | 0.1 – 3.0% | 0.1 – 3.0% | 0.3- 2.0% |
Specifications of Nd:GdVO4 crystal：
Table 4. Specifications
| Dimension Tolerance | (W ± 0.1 mm) × (H ± 0.1 mm) × (L +0.2/-0.1 mm) |
| Clear Aperture | Central 90% of the diameter |
| Flatness | ≦λ/8 @633 nm (L≧2.5 mm)
≦λ/4 @633 nm (L<2.5 mm) |
| Surface Quality (Scratch/Dig) | 10/5 to MIL-PRF-13830B |
| Transmitted Wavefront Distortion | ≦λ/4 @633 nm |
| Parallelism | 20 arc sec |
| Perpendicularity | ≦15 arc min |
| Angle Tolerance | ≦±0.5° |
| Chamfer | ≦0.2 mm × 45° |
| Chip | ≦0.1 mm |
| AR Coating | R<0.2% @1064 nm |
| HR Coating | R＞99.8% @1064 nm, T＞95% @808 nm |
| Quality Warranty Period | One year under proper use. |
