Chromium Doped Yttrium Aluminum Garnet Cr4+:YAG Crystal
A High Power, Solid State and Compact Passive Q-switch
Passive Q-Switching is preferred for simplicity of manufacturing and operation, low cost and reduced system size and weight. Cr4+: YAG (Y3Al5O12) is an excellent crystal for passively Q-switching diode pumped or lamp-pumped Nd: YAG, Nd: YLF, Yb: YAG or other Nd and Yb doped lasers at wavelength from 1.0 to 1.2 mm. Because of its chemically stable, durable, UV resistant, good thermal conductivity and high damage threshold (> 500 MW/cm2) and being easy to be operated, it will replace traditional materials, such as, LiF, organic Dye and color centers.
| Basic Properties of Cr4+:YAG | |
| Formula | Cr4+:Y3Al5O12 |
| Crystal Structure | Cubic Garnet |
| Dopant Level | 0.5 mol% ~ 3 mol% |
| Hardness | 8.5 (Mohs) |
| Damage Threshold | > 500 MW/cm2 |
| Refractive Index | 1.82 @ 1064 nm |
| Main Specifications | |
| Flatness | < λ/8 |
| Wavefront Distortion | λl/4 |
| Parallelism | < 30” |
| Surface quality | 20/10 scratch/dig |
| AR-coating | R<0.2% @ 1064 nm |
| Standard Aperture | 3X3 ~ 10X10 mm |
AR-coatings and HR-coatings are also available. We can control the initial transmission (To) from 10% to 95% according to customer’s requirements. The preliminary experiments of WTS's Cr4+: YAG showed that the pulse width of passively Q-switched lasers could be as short as 9 ns for diode pumped Nd: YAG lasers and repetition as high as 10 kHz for diode pumped Nd: YVO4 lasers. Furthermore, an efficient green output at 532 nm, and UV output at 355 nm and 266 nm were generated, after a subsequent intracavity SHG in KTP for diode pumped and passive Q-switched Nd: YAG and Nd:YVO4 lasers.
Cr4+: YAG is also a laser crystal with tunable output from 1.35 mm to 1.6 mm. It can generate ultrashort pulse laser (to fs pulsed) when pumped by Nd: YAG laser at 1.064mm.