Crystal growth and characterization of a new quaternary hexagonal nonlinear crystal for the mid-IR: Ba2Ga8GeS16

• Hexagonal Ba2Ga8GeS16 (B2GGS) grown by vertical Bridgman-Stockbarger. • Refractive indices of uniaxial B2GGS measured. • Transmission of B2GGS measured. • Nonlinear coefficient of B2GGS measured. • Second-harmonic generation (SHG) in B2GGS realized. The non-centrosymmetric hexagonal Ba 2 Ga 8 GeS 16 (B2GGS) crystal is grown for the first time with good optical quality by the vertical Bridgman-Stockbarger technique. The linear (transmission, dispersion, and birefringence) and nonlinear (second order susceptibility) properties of this new uniaxial nonlinear crystal for the mid-IR part of the spectrum are studied.