High-intensity third-harmonic generation

Abstract

The azimuthal dependence of third-order and cascaded second-order nonlinear coupling are used to measure the relative contributions of each to direct third-harmonic generation in β-barium borate. This enabled the measurement of the values of χ10(3),χ11(3), and χ16(3) relative to the known χij(2). Finally, conversion efficiencies to 3ω of up to 6% from a single crystal were achieved with a femtosecond chirped-pulse-amplification laser with 200 GW/cm2 in collimated beams.