| Amorphous Materials Inc. |
Your Source for IR Materials |
GALLIUM ARSENIDEGallium Arsenide is prepared at Amorphous Materials by two methods: Horizontal Bridgman and Vertical Bridgman. Materials may be doped or undoped, single or polycrystalline. IR optical lens blanks are furnished as semi-insulating material. All material is 100% tested to assure an absorption coefficient of 0.01 cm -1 or less. Laser calorimetry measurements are used to verify the quality of high energy laser grade material. Large area rectangular windows, up to 6" x 12" , are prepared using a Horizontal Bridgman technique. The material can be doped or undoped materials may be provided. |
GENERAL PROPERTIES OF GALLIUM ARSENIDE
| Density | 5.31 gms/cm3 |
| Thermal Expansion | 6 X 10-6/ºC |
| Hardness (Knoop) | 750 |
| Rupture Modulus | 10,436 psi |
| Thermal Conductivity | 0.37 W/ cm sec ºK |
| Specific Heat | 0.076 cal / gm ºK |
| Molecular Weight | 144.63 |
| Structure | cubic |
| Melting Point | 1238ºC |
| Dielectric Constant | 12.5 |
| Energy Gap | 1.38 ev @ 25ºC |
|
WAVELENGTH
µm |
REFRACTIVE (1)
INDEX @ 25º C |
ABSORPTION
COEFFICIENT cm-1 |
| 1.0 | 3.5091 | 1.74 |
| 1.064 | 3.4774 | 1.41 |
| 1.25 | 3.4188 | 0.45 |
| 1.50 | 3.3777 | 0.061 |
| 1.75 | 3.3549 | 0.011 |
| 2.0 | 3.3409 | 0.01 |
| 2.5 | 3.3256 | 0.01 |
| 3 | 3.3161 | 0.01 |
| 4 | 3.3066 | 0.01 |
| 5 | 3.3010 | 0.01 |
| 6 | 3.2966 | 0.01 |
| 7 | 3.2924 | 0.01 |
| 8 | 3.2881 | 0.01 |
| 9 | 3.2834 | 0.01 |
| 10 | 3.2782 | 0.01 |
| 11 | 3.2725 | 0.01 |
| 12 | 3.2661 | 0.03 |
| 13 | 3.2589 | 0.41 |
| 14 | 3.2508 | 0.23 |
V3-5 = 145 V8-12 = 107
Measured optical homogeneity for 100mm diameter plates 50mm thick was
± 65 X 10-6 or DN/N = 20 X 10-6 (Scott Sullivan, Exotic Materials, 1991)
(1) Hilton (1975), Horizontal Bridgman, Parrallel to Growth Axis
|
THERMAL CHANGE IN REFRACTIVE INDEX DN / D T ºC X 106 |
|---|
| Wavelength µm | (LOW) | (HIGH ) |
| 3 | 161±4 | 206±1 |
| 5 | 159±5 | 216±3 |
| 8 | 157±5 | 208±11 |
| 10 | 148±7 | 202±14 |
| 12 | 153±6 | 210±15 |
