# BaGa4Se7 (BGSe)

BaGa4Se7, commonly abbreviated as BGSe, is a chalcogenide-based nonlinear optical crystal known for its phase-matching capabilities and broad transparency window. This material is particularly suited for frequency conversion applications in the mid-infrared region, including second-harmonic generation (SHG), sum-frequency generation (SFG), and optical parametric oscillation (OPO). BGSe exhibits high nonlinear optical coefficients, as well as a high laser damage threshold, making it well-suited for high-power applications. The crystal is generally grown using techniques like the Bridgman-Stockbarger method, and can be cut and polished into high-quality facets for optimal performance. One important consideration for this material is its sensitivity to moisture and other environmental factors; thus, careful handling and storage are required to maintain its optical properties. Overall, BGSe offers a compelling combination of properties that make it a valuable material for nonlinear optics, especially for applications requiring high efficiency and broad tunability in the mid-infrared range.

## External links

- BaGa4Se7 - DienTech