Nd:YVO4 crystal is one of the most excellent laser host materials, it is suitable for diode laser-pumped solid state laser. Compactly designed Nd3+ :YVO4 lasers with green, red and blue light output are really perfect means for material processing. Nd3+ :YVO4 diode pumped lasers have: wide absorption bandwidth, low lasing threshold, high slope efficiency, large luminescent cross-section, linearly polarized emission and single-mode output.
Advantages
Lower lasing threshold and higher slope efficiency
Low dependency on pumping wavelength and tend to single mode output
Large stimulated emission cross-section at lasing wavelength
High absorption over a wide pumping wavelength bandwidth
Optically uniaxial and large birefringence emit strongly-polarized laser
Main Types of Diffusion Bonded Crystals
| Crystal Structure | Zircon Tetragonal, Space Group D4h |
| Lattice Parameters | a=b=7.12Å, c=6.29Å |
| Dopant Level | 0.1~3.0 atm% |
| Density | 4.22g/cm3 |
| Mohs Hardness | 4.6~5, Glass-like |
| Refractive Indices | no=1.9573, ne=2.1652 @1064nm |
| Thermal Expansion Coefficient | αa=4.43×10-6/K, αc=11.37×10-6/K |
| Thermal Conductivity Coefficient | ∥c:5.23W/m/K, ⊥c:5.10W/m/K |
| Lasing Wavelengths | 914nm, 1064nm, 1324nm |
| Thermal Optical Coefficient | dno/dT=8.5×10-6/K, dne/dT=3.0×10-6/K |
| Stimulated Emission Cross-section | 25.0×10-19cm2 @1064nm |
| Fluorescent Lifetime | 90μs @808nm |
| Absorption Coefficient | 31.4cm-1 @808nm |
| Absorption Length | 0.32mm @808nm |
| Instrinsic Loss | Less 0.1%cm-1@1064nm |
| Gain Bandwidth | 0.96nm (257GHz) @1064nm |
| Polarized Laser Emission | π polarization, Parallel to optic axis |
| Diode Pumped Optical to Optical Efficiency | >60% |
Specifications of Nd:YVO4
| Flatness | ＜λ/10@632.8nm |
| Parallelism | ≤10" |
| Perpendicularity | ≤5" |
| Surface Quality | 10-5 S/D |
Dimensional Tolerance | Rod: Dia+/-0.1mm, L+/-0.25mm |
| Slab: +/-0.1mm | |
| Coating | Upon request |
| Damage Threshold | ≥1GW/cm ² |
Nd:YAG crystal is the most early and mature laser material adopted by R&D, medical, industrial and military customers. It is the ubiquitous presence for near-infrared solid-state lasers and their frequency-doubler, tripler, and higher order multiplier.
Advantages
High Gain,High Efficiency,Low Threshold
High Optical Quality and low Loss at 1064nm
Good Mechanical and Thermal Properties
Easy to operate with TEM00 mode(Q-Switch,pulsed,CW)
Main Properties of Nd:YAG Crystal
| Chemical Formula | Nd:Y3Al5O12 |
| Crystal Structure | Cubic Garnet |
| Dopant Level | 0.6~1.3 atm% |
| Melting Point | 1970ºC |
| Density | 4.56 g/cm3 |
| Mohs Hardness | 8.5 |
| Refractive Index | 1.82@1064nm |
| Thermal Expansion Coefficient | 7.8x10-6/K [111], 0-250ºC |
| Thermal Conductivity | 14W/m/K @20ºC, 10.5W/m/K @100ºC |
| Loss Coefficient | 0.003cm-1@1064nm |
| Lasing Wavelength | 1064nm |
| Pump Wavelength | 807.5nm |
| Refraction Time of Terminal Lasing Level | 30ns |
| Radiative Lifetime | 550µs |
| Fluorescence Lifetime | 230µs |
| Effective Emission Cross Section | 2.8x10-19cm2 |
| Polarized Emission | Unpolarized |
| Thermal Birefringence | High |
Specifications of Nd:YAG
| Flatness | <λ/10@632.8nm |
| Paralellism | ≤10'' |
| Perpendicularity | ≤5' |
| Surface Quality | 10-5 S/D |
| Optical Quality | Interference fringes<0.125/inch |
| Extinction ration Ø3~Ø6.35>28dB, Ø7~ Ø10>25dB | |
| Dimensional Tolerance | Rod: Dia+/-0.1mm, L+/-0.25mm |
| Slab: +/-0.1mm | |
| AR-coating | R<0.2%(@1064nm) |
| HR-Coating Reflectivity | R>99.8%@1064nm and T>95%@808nm |
| Other HR Coatings | HR@1064/532nm, HR@946nm, HR@1319nm |
| and other wavelengths are also available | |
| Damage Threshold | ≥500MW/cm ² |
Cr4+ :YAG Crystal is an excellent crystal for passively Q-switching diode pumped or lamp-pumped Nd:YAG , Nd:YLF, Nd:YVO4 or other Nd and Yb doped lasers at wavelength from 0.8 to 1.2µm. Passive Q-switches or saturable absorbers provide high power laser pulses without electro-optic Q-switches, thereby reducing the package size and eliminating a high voltage power supply. Cr4+ :YAG is more robust than dyes or color centers and is the material of choice for 1 um Nd lasers.
Main Properties of Cr4+:YAG Crystal
| Chemical Formula | Cr4+:Y3Al5O12 |
| Crystal Structure | Cubic Garnet |
| Dopant Level | 0.5~3 atm% |
| Mohs Hardness | 8.5 |
| Melting Point | 1970ºC |
| Density | 4.55 g/cm3 |
| Refractive Index | 1.82@1064nm |
| Themal Expansion Coefficient | 8.2x10-6/K[100], 7.7x10-6/K[110] |
| Thermal Conductivity | 12.13 W/m/K @25ºC |
| Fluorescence Lifetime | 3.4µs |
| Base State Absorption Cross Section | 4.3x10-18cm2 |
| Emission State Absorption Cross Section | 8.2x10-19cm2 |
Specifications of Cr4+:YAG
| Flatness | <λ/10 |
| Parallelism | ≤10" |
| Perpendicularity | ≤5´ |
| Surface Quality | 20-10 S/D |
| Initial Transmittance | 1%～98% |
| Dimensional Tolerances | Rod: Dia+/-0.1mm, L+/-0.25mm |
| Slab: +/-0.1mm | |
| Coating | Upon request |
| Damage Threshold | ≥500 MW/cm² |
Diffusion Bonded Crystals are crystals consisting of two, three or more parts with different dopant levels. Usually, doped and undoped materials are used. Difussion Bonded Crystals are used to decrease thermal lensing effect considerably. This bonding technology in laser applications can not only greatly improve the laser performance and beam quality, but also conducive to the intergration of laser systems and access to large-size crystal.
Advantages
Decrease thermal effect
Improve efficiency
High damage threshold
Improve beam quality
Compact size
Main Types of Diffusion Bonded Crystals
| Material | Doping Concentration | Aperture(mm2) | Length(mm) |
| YAG+Nd:YAG | 0.6~1.3% | 2x2-20x20 | 2-200 |
| YAG+Cr4+:YAG | 0.5~3% | 2x2-20x20 | 2-50 |
| Nd:YAG+Cr4+:YAG | 0.6~1.3%/0.5~3% | 2x2-20x20 | 2-200 |
| YAG+Nd:YAG+YAG | 0.6~1.3% | 2x2-20x20 | 3-200 |
| YAG+Nd:YAG+Cr4+:YAG | 0.6~1.3%/0.5~3% | 2x2-20x20 | 3-200 |
| YAG+Nd:YAG+Cr4+:YAG+YAG | 0.6~1.3%/0.5~3% | 2x2-20x20 | 5-200 |
| YVO4+Nd:YVO4+YVO4 | 0.1~3% | 2x2-10x10 | 1-20 |
| YVO4+Nd:YVO4+YVO4 | 0.1~3% | Φ2-10 | 3-20 |
Specifications of Nd:YVO4+YVO4
| Flatness | <λ/10 |
| Parallelism | ≤20" |
| Perpendicularity | ≤15´ |
| Surface quality | 20-10 S/D |
| Dimensional tolerances | +/-0.1mm |
| Coating | Upon request |
Specifications of Nd:YAG+YAG+Cr:YAG
| Flatness | <λ/10 |
| Parallelism | ≤10" |
| Perpendicularity | ≤10´ |
| Surface quality | 20-10 S/D |
| Dimensional tolerances | +/-0.1mm |
| Coating | Upon request |
Specifications of Diffusion Bonded Crystals
| Flatness | <λ/10 |
| Parallelism | ≤10" |
| Perpendicularity | ≤5´ |
| Surface quality | 20-10 S/D |
| Dimensional tolerances | +/-0.1mm |
| Coating | AR or HR Coating |
