Er:YAG is an excellent laser crystal which lasers at 2.94µm. It has wide applications in medical laser systems, and others.
Very high slope efficiency
Operates well at room temperature
Operate in a relatively eye-safe wavelength range
Basic Properties:
Crystal Structure |
Cubic |
Lattice Parameters |
12.01 Å |
Melting Point |
1970 °C |
Moh Hardness |
8.5 |
Density |
4.56±0.04g/cm 3 |
Specific Heat (0-20) |
0.59J/g.cm 3 |
Modulus of Elasticity |
310GPa |
Young's Modulus |
3.17X10 4 Kg/mm 2 |
Poisson Ratio |
0.3(est.) |
Tensile Strength |
0.13~0.26GPa |
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 Optical Coefficient (dn/dT) |
7.3×10 -6 / °C |
Thermal Shock Resistance |
790W/m |
The Sellmeier equations (°C in µm for YAG):
n ^2 = 2.08745 + 1.2081 °l ^2 /(°l^ 2 - 0.02119 )+ 17.2049 °l ^2 /(°l ^2 - 1404.45 )
Optical and Spectral Properties
Dopant concentration |
Er: ~50 at% |
Laser Transition Transition |
4 I 11/2 to 4 I 13/2 to 4 I 13/2 |
Laser Wavelength |
2940nm |
Photon Energy |
6.75×10 -20 J(@2940nm) |
Emission Cross Section |
3×10 -20 cm 2 |
Index of Refraction |
1.79 @2940nm |
Pump Bands |
600~800 nm |
Er:YAG's Specifications:
Orientation: |
<111> or <100]> crystalline within 5° |
Wavefront distortion : |
l /8 per inch @ 633 nm |
Extinction Ratio: |
>25dB |
Dimension Tolerances |
Rods with diameter: ±0.025 mm , Length: ±0.5 mm |
Surface quality: |
10/5 Scratch / Digper MIL-O-1380A |
Parallelism: |
< 10 arc seconds |
Perpendicularity: |
< 5 arc minutes |
Flatness: |
< l /10 @ 633 nm |
chamfer: |
<0.1 mm @ 45deg. |
Barrel Finish: |
50-80 micro-inch (RMS) , |
AR Coating Reflectivity |
< 0.25% |
Note: The other specification and dimension is available too |