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Yttrium Aluminium Garnet YAG
YAG (Yttrium aluminium oxide Y3Al5O12) is an active laser crystal when dopants such as Nd, Tm, Er, and Cr are used. Being cubic there is no double refraction and it is sometimes used for a window material substituting for sa
| Transmission Range | 0.21 to 5.5 μm |
|---|---|
| Refractive Index | 1.81523 at 1.06 μm (1) |
| Reflection Loss | 16.7% at 1.06 μm (2 surfaces) |
| Absorption Coefficient | n/a |
| Reststrahlen Peak | n/a |
| dn/dT | +9.1 x 10-6 K-1 @ 1.06 μm (2) |
| dn/dμ | 0 |
| Density | 4.56 g/cc |
| Melting Point | 1940°C |
| Thermal Conductivity | 12.9 W m-1 K-1 |
| Thermal Expansion | 7.8 (111), 7.7 (110), 8.2 x 10-6 K-1 (100) |
| Hardness | Knoop 1215 |
| Specific Heat Capacity | 590 J Kg-1 K-1 |
| Dielectric Constant | 11.7 |
| Youngs Modulus (E) | 300 GPa |
| Shear Modulus (G) | n/a |
| Bulk Modulus (K) | n/a |
| Elastic Coefficients | C11 = 333 C12 = 111 C44 = 115 |
| Apparent Elastic Limit | 280 MPa |
| Poisson Ratio | 0.28 |
| Solubility | Insoluble in water |
| Molecular Weight | 593.52 |
| Class/Structure | Cubic Garnet, m3m |
| μm | No | μm | No | μm | No |
|---|---|---|---|---|---|
| 0.266 | 1.9278 | 1.030 | 1.8173 | 2.014 | 1.8123 |
| 0.354 | 1.8725 | 1.064 | 1.8169 | 2.097 | 1.8121 |
| 0.532 | 1.8368 | 1.333 | 1.8146 | 2.123 | 1.8113 |
| 0.800 | 1.8245 | 1.444 | 1.8140 | 2.940 | 1.8113 |
| 0.808 | 1.8217 | 1.500 | 1.8137 | ||
| 0.946 | 1.8186 | 1.640 | 1.8132 |
YAG crystal is produced by the Czochralski growth process up to approximately 100mm diameter.
REFERENCES:
(1) Handbook of Optical Constants, ed Palik, V3, ISBN 0-12-544423-0
(2) Wilson, Thermo-Optic Coefficients. PhD dissertation. U Southern Calif. Jan 1980