In the Cr,Er: YSGG crystal ,Cr3+ replaces the Ga3+ or Sc3+，and Y3+ is replaced by Er3+, the crystal has the advantages of large size, low optical damage, high optical quality and low lasing threshold. Flashlamp or laser diode is often used to pump the laser crystal, 970 nm laser diode is regarded as the first choice to realize 2790 nm laser pumping of Er, Cr: YSGG, which can excite the Er3+ to his lasing upper level directly with high efficiency and low energy cost. Nowadays, various of method have been adopted to switch Q (such as acousto-optic, electro-optic, FTIR) to realize pulse laser output. Owing to the specificity of lasing wavelength, this kind of lasers are widely used in medical applications, scientific investigations, material processing, military and so on.
Parameter
| Crystal Structure | Cubic |
| Chemical Formula | Y2.93Sc1.43 Ga3.64O12 |
| Lattice Constant | 12.42 Å |
| Concentration | 30 at % (3.7 x 1021 cm-3 , dodecahedral Er3+) |
| 2 at % (1.7 x 1020 cm-3 , octahedral Cr3+) | |
| Wavefront Distortion (per inch of rod length) | 1/2 |
| Surface Quality | 10 – 5 scratch-dig |
| Perpendicularity | 5 ‘ |
| Parallelism | 30〞 |
| Barrel Finish | 55 micro-inch ±5 micro-inch |
| Chamfer Angle | 45 deg ±5 deg |
| Chamfer | 0.005 ±0.003 in |
| Length Tolerance | +0.040 / -0.000 in |
| Diameter Tolerance | +0.0000 / -0.0020 in |
| Thermal conductivity（W/mK） | 8 |
| Thermal expansion coefficient | 8.1×10-6/K |
| Thermo-optical factor（dn/dT）（10-6/K） | 12.3 |
| Hardness（Mohs） | 8 |
| Density | 5.67g/cm3（Cr&Er doped） |
| Sizes, (dia x length), mm | from 3 x 30 to 12.7 x 127.0 |
| Orientation | <001>, <111> |
| Refractive index | 1.92 at 1000nm |
| Fluorescent Lifetime | 1400 μs |
| Emission cross-section, cm2 | 5.2 x 10-21 |
| Lasing wavelength, µm | 2.791 |
- Good crystal quality
- Super mechanical properties
- Low pump threshold
- High slope efficiency
- Working at medium frequency
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