High-quality crystals of BGSe (BaGa4Se7), a newly developed IR nonlinear optical (NLO) material, were obtained via the Bridgman–Stockbarger technique. This crystal exhibits high transmittance over the wide range of 0.47–18 μm, except for an absorption peak at around 15 μm

And BGSe (BaGa4Se7) crystal exhibits a powder second harmonic generation (SHG) response that is approximately 2–3 times that of AgGaS2. The surface laser damage threshold is about 3.7 times that of AgGaS2 crystal under identical conditions.

Advantages for IR laser output:

Suitable for various pumping source (1-3μm)

Wide tunable IR output range (3-18μm)

OPA, OPO, DFG, intracavity/extravity, cw/pulse pumping

Basic properties:
space group Pc
Transmission range 0.47-18μm
Major NLO coefficient 
d11 = 24 pm/V
Birefringence @2μm 0.07
Damage threshold (1μm, 5ns ) 550MW/cm2