AgGaS2


Melting Point                                851 °C

Density                                        5.700 g/cm3

Mohs Hardness                            3-3.5

Wavefront distortion                    less than λ/6 @ 633 nm

Flatness                                       λ/6 @ 633 nm

Surface Quality                            20/10

Parallelism                                   better than 1 arc min

Perpendicularity                          5 arc minutes









AGS is transparent from 0.53 to 12 µm. Although its nonlinear optical coefficient is the lowest among the mentioned infrared crystals, high short wavelength transparency edging at 550 nm is made use of in OPOs pumped by Nd:YAG laser; in numerous difference frequency mixing experiments with diode, Ti:Sapphire, Nd:YAG and IR dye lasers covering 3–12 µm range; in direct infrared countermeasure systems, and for SHG of CO2 laser. Thin AgGaS2 (AGS) crystal plates are popular for ultrashort pulse generation in mid IR range by difference frequency generation employing NIR wavelength pulses.

Applications
  • Generation second harmonics on CO and CO2 - lasers
  • Optical parametric oscilator
  • Different frequency generator to middle infrared regions up to 12 mkm.
  • Frequency mixing in the middle IR region from 4.0 to 18.3 µm
  • Tuneable solid state lasers (OPO pumped by Nd:YAG and others lasers operating in 1200 to 10000 nm region with efficiency 0.1 to 10 %)
  • Optical narrow-band filters in the region near isotropic point (0.4974 m at 300 °K), transmission band being tuned at temperature variation 
  • Up-conversion of CO2 laser radiation image into near-IR or visible region by using/ or use of Nd:YAG, ruby or dye lasers with efficiency up to 30 %

Basic properties

Crystal Structure

Tetragonal

Cell Parameters 

a=5.992 Å, c=10.886 Å

Melting Point

851 °C

Density 

5.700 g/cm3

Mohs Hardness

3-3.5

Absorption Coefficient

<0.05 cm-1 @ 1.064 µm
<0.02 cm-1 @ 10.6 µm

Relative Dielectric Constant @ 25 MHz

ε11s=10.5
ε11t=12.0

Thermal Expansion Coefficient 

||C: -8.1 x 10-6 /°C
⊥C: +19.8 x 10-6 /°C

Thermal Conductivity 

1.0 W/M/°C

Linear Optical Properties

Transparency Range

0.50-13.2 um

Refractive Indices
@ 1.064 um
@ 5.300 um
@ 10.60um

no
2.4521
2.3945
2.3472

ne
2.3990
2.3408
2.2934

Thermo-Optic Coefficients

dno/dt=15.4 x 10-5/°C
dne/dt=15.5 x 10-5/°C

Sellmeier Equations
(ʎ in um)

no2=3.3970+2.3982/(1-0.09311/ʎ2)+2.1640/(1-950/ʎ2)
ne2=3.5873+1.9533/(1-0.11066/ʎ2)+2.3391/(1-1030.7/ʎ2)

Nonlinear Optical Properties

Phase-Matching SHG Range

1.8-11.2 um

NLO Coefficients @ 1.064 um

d36=d24=d15=23.6 pm/V

Linear Electro-optic Coefficients

Y41T=4.0 pm/V
Y63T=3.0 pm/V

Damage threshold
@ ~ 10 ns, 1.064 um

25 MW/cm2(surface),

500 MW/cm2(bulk)

Basic Parameters

Wavefront distortion

 less than λ/6 @ 633 nm

Dimension tolerance

(W +/-0.1 mm) x (H +/-0.1 mm) x (L +0.2 mm/-0.1 mm)

Clear aperture

> 90% central area 

Flatness

 λ/6 @ 633 nm for T>=1.0mm

Surface Quality

 Scratch/dig 20/10 per MIL-O-13830A 

Parallelism

better than 1 arc min

Perpendicularity

5 arc minutes

Angle tolerance

Δθ < +/-0.25oΔφ < +/-0.25o

Customized

You can customise this product to your needs. If you do not find suitable specifications for your application please contact us for custom solution.