Nonlinear optical crystal AGSe (AgGaSe2)


(silver gallium selenide)


Main properties

Compound AgGaSe2
Transparency range, µm 0.76 – 18
Negative uniaxial crystal no > ne (at λ < 0.804 μm ne > no)
Nonlinear coefficient, pm/V d36 = 39.5 @10,6 µm 
Symmetry Tetragonal, -42m point group

10.6 µm
5.3 µm
no=2.5915, ne=2.5582 no=2.6138, ne=2.5811
Optical Damage Threshold, MW/cm2
2000 nm
(t=30 ns)
Walk off angle, ° 5.3 µm 0.68
Thermal conductivity k, WM/M°C 1.1
Band-gap energy, eV 1.8
Optical activity ρ = 7deg/mm at isotropic point, μm n0= ne, λ = 0.804

The parameters of optical elemets

Orientation accuracy, arc min < 30
Parallelism, arc sec < 40
Flatness 546 nm λ/4
Surface quality, scratch/dig   30/20


  • Efficient frequency doubling for mid-IR radiation
  • Optical parametric oscilation and amplification, Different frequency generation to mid-infrared regions up to 17 µm
  • Optical narrow-band filters in the region near isotropical point (0.804 µm at 300 K)

Large/long optical elements are available, please, send your requests.

We are able to provide suitable Anti-reflection / Protective, etc. coatings tailored to customer’s specifications, reflectivity curves are applied upon request.