β-Barium borate (β-BaB2O4 or BBO) is a nonlinear optical crystal which combines a number of unique features. These features include broad transmission and phase matching ranges, large nonlinear coefficient, high damage threshold, high quality single crystals and excellent optical homogeneity. Therefore, Beta-BaB2O4 provides an attractive solutions for various nonlinear optical applications. Besides, BBO is one of the best candidates for electro-optical applications due to its excellent electro-optical properties.
BBO crystals have been widely used in non-linear optical applications like OPO, OPA, OPCPA and other. Thanks to its large spectral transmission range as well as phase matching, BBO crystals have been applied in second, third, fourth or fifth harmonic generations for high power visible/UV sources and optical parametric conversions for high power broadly tunable sources. Since its broad gain bandwidth overlaps with Ti:Sapphire in 800 nm range, ultra-high power and high contrast laser systems have been built based on the mixed CPA/OPCPA plan.