Features
Wide transmission region from 0.74 um to 12um
Large nonlinear coefficient
Good mechanical and physical properties
Relatively high damage threshold
Phase matchable over a broad spectral region
High thermal conductivity
Applications
Second, third, and fourth harmonic generation of CO2 laser
Optical parametric generation (OPO) with pumping at a wavelengths of 2.05-2.94 m and possibility to generate effectively 3-10 m ranges
Second harmonic generation of CO-laser
Producing coherent radiation in sub-millimeter-range from 70.0 m to 1000 m - terahertz range
Generation of combined frequencies of CO2- and CO-lasers radiation and other lasers are working in the crystal transparency region
Chemical and Physical Properties
|
Property |
Value |
|
Chemical formula |
ZnGeP2 |
|
Crystal structure |
Tetragonal,`42m |
|
Lattice Parameter |
a=b=5.467, c=12.736 |
|
Mass density |
4.16 g/cm3 |
|
Moh hardness |
5.5 |
|
Melting point |
About 1040°C |
|
Thermal conductivity |
180 W/m/K |
|
Thermal expansion coefficient |
‖,5x10-6/K; ⊥,7.8x10-6/K |
|
Birefringence |
positive uniaxial |
Linear Optical Properties
|
Property |
Value |
|
Transparency Range |
0.74 - 12 um |
|
Absorption Coefficient: |
<0.05cm-1 @2050-2100 nm |
|
Refractive Indices @ 2.05 um @ 2.79 um @ 5.30 um @ 10.6 um |
no = 3.1478, ne = 3.1891 no = 3.1333, ne = 3.1744 no = 3.1136, ne = 3.1547 no = 3.0729, ne = 3.1143 |
|
Sellmeier Equations( in m) |
no2() = 4.64467+5.10087/(2-0.13656)+4.277772/(2-1653.89) ne2() = 4.71539+5.26358/(2-0.14386)+2.373102/(2-1000.82) |
Nonlinear Optical Properties
|
Property |
Value |
|
SHG Phase Matchable Range |
3177 10357nm (Type I) |
|
NLO coefficients |
d36=758 pm/V Typedeeo=d36 sin2cos2 Typedoeo=deoo=d36 sinsin2 |
|
Damage Threshold at 2.79 um at 10.6 um |
30 GW/cm2 (150 ps) 1 GW/cm2 (2 ns) |
Polishing Specification
|
Property |
Value |
|
Orientation Tolerence |
< 0.5° |
|
Thickness/Diameter Tolerance |
±0.05 mm |
|
Surface Flatness |
</8@632 nm |
|
Wavefront Distortion |
</4@632 nm |
|
Surface Quality |
10/5 |
|
Parallel |
30 |
|
Perpendicular |
15 |