+86 21 51012729
info@bbotech.com
Yb:YAG is one of the most promising laser-active materials and more suitable for diode-pumping than the traditional Nd-doped systems. Compared with the commonly used Nd:YAG crystal, Yb:YAG crystal has a much larger absorption bandwidth to reduce thermal management requirements for diode lasers, a longer upper-laser level lifetime, three to four times lower thermal loading per unit pump power. Yb:YAG crystal at 1030nm is a good substitute for Nd:YAG crystal at 1064nm and its second harmonic at 515nm may replace Ar-ion laser(with a large volume), which emits at 514nm.
Yb:YAG Crystal Features:
- Very low fractional heating, less than 11%
- Very high slope efficiency
- Broad absorption bands, about 8nm@940nm
- No excited-state absorption or up-conversion
- Conveniently pumped by reliable InGaAs diodes at 940nm(or 970nm)
- High thermal conductivity and large mechanical strength
Yb:YAG Crystal Physical Properties:
|
Crystal Structure |
Cubic |
|
Lattice Parameters |
12.01 Å |
|
Melting Point |
1970 °C |
|
Moh Hardness |
8.5 |
|
Density |
4.56±0.04 g/cm3 |
|
Specific Heat (0-20) |
0.59 J/g.cm3 |
|
Modulus of Elasticity |
310 GPa |
|
Young's Modulus |
3.17 x 104 Kg/mm2 |
|
Poisson Ratio |
0.3(est.) |
|
Tensile Strength |
0.13~0.26 GPa |
|
Thermal Expansion Coefficient |
[100]Direction:8.2x10-6 / °C (0~250 °C ) [110]Direction:7.7x10-6 / °C (0~250 °C ) [111]Direction:7.8x10-6 / °C (0~250 °C ) |
|
Thermal Conductivity |
14W/m/K(@20 °C ) 10.5W/m/K(@100 °C ) |
|
Thermal Shock Resistance |
790W/m |
Yb:YAG Crystal Optical Properties:
|
Dopant concentration |
Yb: 0.5 ~ 25 at% |
|
Laser Transition |
2F5/2 -> 2F7/2 |
|
Laser Wavelength |
1030nm |
|
Photon Energy |
1.93×10-19J (@1030nm) |
|
Emission Linewidth |
9nm |
|
Emission Cross Section |
2.0×10-20cm2 |
|
Fluorescence Lifetime |
1.2 ms |
|
Diode Pump Band |
940nm or 970nm |
|
Pump Absorption Band Width |
8 nm |
|
Index of Refraction |
1.82 |
|
Thermal Optical Coefficient |
9 × 10-6/ °C |
|
Loss Coefficient |
0.003 cm-1 |
Yb:YAG Standard Product Specifications:
|
Orientation |
<111> or <100> crystalline within 5° |
|
Wavefront distortion |
λ /8 @ 633 nm |
|
Extinction Ratio |
>25dB |
|
Dimension Tolerances |
Diameter: ±0.025 mm, Length: ±0.5 mm |
|
Surface quality |
10/5 Scratch / Dig per MIL-O-1380A |
|
Parallelism |
< 10 arc seconds |
|
Perpendicularity |
< 5 arc minutes |
|
Flatness |
< λ /10 @ 633 nm |
|
Chamfer |
<0.1 mm @ 45deg. |
|
Barrel Finish |
Ground Finish: 400# Grit |
|
AR Coating Reflectivity |
0.25% @ 1030nm |