Introduction of Nd:YVO4
Nd:YVO4(Neodymium Doped Yttrium Orthovanadate) is a crystalline material with excellent performance and is suitable for manufacturing all-solid-state laser diode pumped lasers. The lasing property of Nd:YVO4 is mainly due to the presence of neodymium ions, which can be excited by infrared or visible light at a wavelength of 1064nm. Among the current commercial laser crystals of low or middle power density, Nd:YVO4 is regarded as the most efficient laser host crystal for diode pumping. Compared with Nd: YAG, it has higher absorption coefficient and emission feature.
|Atomic Density||1.26×1020 atoms/cm3 (Nd1.0%)|
|Zircon Tetragonal, space group D4h-I4/amd
|Mohs Hardness||4-5 (Glass-like)|
|Thermal Expansion Coefficient（300K）||αa=4.43×10-6/K
|Thermal Conductivity Coefficient（300K）||∥C：0.0523W/cm/K
|Thermal optical coefficient（300K）||dno/dT=8.5×10-6/K
|Stimulated emission cross-section||25×10-19cm2 @ 1064nm|
|Absorption coefficient||31.4cm-1 @810nm|
|Intrinsic loss||0.02cm-1 @1064nm|
|Polarized laser emission||polarization; parallel to optical axis (c-axis)|
|Diode pumped optical to optical efficiency||>60%|
|Sellmeier equations（λ in μm）||no2=3.77834+0.069736/(λ2-0.04724)-0.010813λ2
Product Features of Photonchina：
- Responsive delivery
Applications of Nd:YVO4
Pumped by laser diodes, Photonchina’s Nd:YVO4 crystal has been usually used together with high NLO coefficient crystals ( LBO, BBO, or KTP) to frequency-shift the output from the near infrared to green, blue, and even UV. This incorporation to build solid-state lasers contributes to various applications: machining, medical inspection, material processing, spectroscopy, light displaying, laser printing, etc. It has been shown that Nd:YVO4 based diode pumped solid-state lasers are rapidly replacing water-cooled ion lasers and lamp-pumped lasers, especially when compact structure and single-longitudinal-mode outputs are emphasized.
- Standard size: 3x3x0.5mm; 3x3x4mm; 3x3x10mm; 4x4x8mm; 4x4x12mm
- Various doping concentration from 0.1% to 3%;
- Doping concentration tolerance:±0.05%(atm%<1%),±0.1%(atm%≥1%);
- Dimensional tolerance: +/-0.1mm
- Clear aperture: ≥90%
- Flatness: less than λ/8 @633nm (L≥2.5mm); less than λ/4 @633nm (L＜2.5mm)
- Transmitting wavefront distortion: less than λ/4 @633nm
- Chamfer: ≤0.2mm @45°
- Chip: ≤0.1mm
- Scratch/Dig: 10-5, MIL-PRF-13830B
- Parallelism: better than 20 arc seconds
- Perpendicularity: ≤5 arc minutes
- Angle tolerance: ≤0.5°
- Damage threshold[GW/cm2]: ＞1 for 1064nm, TEM00, 10ns, 10Hz (AR-coated)
- Quality warranty period: one year under proper use.
Optical coating services:
- AR/AR-1064/808nm, R<0.2%@1064nm,r＜2%@808nm；
- S1:HR@1064&532 nm, HT808 nm, R>99.8%@1064&532nm, T>90%@808nm;
S2:AR@1064&532 nm, R<0.2%@1064nm, R＜0.5%@532nm;
- S1:HR@1064,HT808, R>99.8%@1064nm,T>95%@808nm;
- S1,S2 AR-coated, S3: gold/chrome plated;
- AR/AR-1064 nm; S3:AR-808 nm;
Note: Other coatings are available upon customer request.
Comparison between Nd:YVO4 and Nd:YAG
1. Nd:YVO4 enjoys 5 times absorption coefficient in a broader absorption bandwidth around the 808nm peak pump wavelength. A smaller size of crystal could therefore be used for the laser, leading to a more compact laser system and also extended lifetime of the expensive laser diode.
2. The broader absorption bandwidth of Nd:YVO4 may reach 2.4 to 6.3 times that of Nd:YAG. In addition to more efficient pumping, it also brings in a broader range of selection of diode specifications which is more desirable for laser system makers, as they will have wider choice when it comes to cost consideration.
3. For stimulated emission cross section, Nd:YVO4 crystal has larger area at 1064nm and 1342nm. When a-axis cut Nd:YVO4 crystal lasing at 1064m, it is about 4 times higher than that of Nd:YAG, while 18 times larger at 1340nm. A CW operation thus completely outperforme Nd:YAG at 1320nm. So Nd:YVO4 laser is easy to maintain a strong single line emission at the two wavelengths.
4. Due to its uniaxial structure, rather than a high symmetry of cubic as Nd:YAG, Nd:YVO4 only emits a linearly polarized laser, thus avoiding undesired birefringent effects on the frequency conversion.
Please see the following table, which clearly indicates the major differences of laser properties between Nd:YVO4 and Nd:YAG。
Table: Comparison of laser properties between Nd:YVO4 vs Nd:YAG
stimulated emission cross-sections (σ), absorption coefficient (α), fluorescent lifetime (τ),
absorption length (Lα), threshold power (Pth); pump quantum efficiency (ηs)