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Passive Q-Switch Crystal Cr:YAG
Overview:
Cr4+:Y3Al5O12 crystal (Cr4+:YAG) is one of the most promising passive Q-switching materials for passively Q-Switching diode pumped or lamped Nd or Yb doped lasers at wavelength from 0.8 to 1.2um. Because of Cr4+:YAG's chemical stability, durability, UV resistance, good thermal conductivity, high damage threshold (> 500 MW/cm ) and easy operation, Cr4+:YAG will replace some traditional switching materials, such as LiF and organic Dye. The preliminary experiments of Cr:YAG showed that the pulse width of passively Q-switched lasers could be as short as 9ns for diode pumped Nd:YAG lasers and repetition rate as high as 10kHz for diode pumped Nd:YVO4 lasers.
General Specifications Of Cr4+:YAG:
| Material |
Cr4+:YAG |
| Orientation |
<111> or <110> or <100> |
| Initial absorption coefficient |
0.5-7/cm@1064nm |
| Diameter tolerance |
Diameter:+0/-0.02mm, W×H:+/-0.1mm |
| Length tolerance |
+/-0.5mm |
| Initial transmittance |
5%-95%@1064nm |
| Dimension |
Diameter:3-12mm, H×W:2×2-30×30mm
(upon customer’s request)
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| Barrel finish |
Ground finish 400#Grit |
| Clear aperture |
>90% central area |
| Parallelism |
<10 arc seconds |
| Perpendicularity |
<5 arc minutes |
| Flatness |
<λ/8@632.8nm |
| Scratch/Dig |
10/5@MIL-0-13830A |
| Anti-Reflection coating |
R<0.15%@1064nm per surface |
| Damage threshold |
>750MW/cm2@1064nm 10ns 10HZ |
Physical and Optical Properties of Cr4+:YAG:
| Crystal Structure |
Cubic |
| Dopant |
0.5~3% Cr |
| Wavelength |
950nm-1100nm |
| Melting Point |
1970℃ |
| Curie Point |
936℃ |
| Density |
4.56g/cm3 |
| Mohs Hardness |
8.5 |
| Recovery Time |
8.5us |
| Thermal Conductivity |
12.13W/m/K |
| Loss Coefficient |
0.003cm-1 |
| Refractive Index |
1.82 @1064nm |
| Base State Absorption Cross Section |
4.3x10-18/cm2 |
| Emission State Absorption Cross Section |
8.2x10-19/cm2 |
| Fluorescence Lifetime |
3.4us |
| Optical Damage Threshold |
>500MW/cm2 |
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